US 3718171 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
.Feb. 27, 1973 R. c. GoDwm I 3,718,171
- moons Filed Sept. 30, 1971 4 Sheets-Sheet 1 lnvenlor Feb. 27, 1973 c, GODWlN 3,718,171
DOORS Filed Sept. 30, 1971 4 Sheets-Sheet 2 1 Inventor Qoq Chants c o'aw-'- Attorneys- Feb. 27, 1973 R, c. GODMN 3,718,171
DOORS Filed Sept. 30, 1971 v 4 Sheets-Sheet 4.
lnuenlor Q05 GUAM/F B 1 QUJMLM'ZM m g- Attorneys United States Patent DOORS Roy Charles Godwin, Ringwood, England, assignor to British Aircraft Corporation Limited, London, England Filed Sept. 30, 1971, Ser. No. 185,255 Claims priority, application Great Britain, Oct. 10, 1970,
Int. Cl.Ed 15/08 US. Cl. 160-210 3 Claims ABSTRACT OF THE DISCLOSURE A door assembly having, a door frame and a door hinged to one edge of the frame. The door comprises two parts hinged together for limited relative rotation, and an actuator effective with the door in the closed POSI- tion operatively connecting the two parts so as to vary the effective depth of the door. The edge of the door remote from the main hinge and the corresponding edge of the door frame being provided with engageable hook means. The relative positions of the hook means being such that when the two parts of the door are set for maximum depth the hook means are disengaged from each other, whilst when the two parts of the door are set to a lesser depth the hook means engage each other to positively lock the door in a closed position.
This invention relates in general to doors and, more particularly, to a door intended primarily for use in pressurised aircraft.
According to the present invention a door assembly in cluding in combination, a door frame, a door to fit the frame, first hinge means pivotally connecting one edge of said door to one edge of said frame for pivotal movement relative thereto about a first hinge axis, said door being formed of two parts, and second hinge means pivotally connecting said two parts for pivotal movement relative thereto about a second hinge axis parallel to said first hinge axis, actuating means effective with said door in the closed position, for causing limited relative movement of said two parts about said second hinge axis in a sense to vary the effective depth of said door, engageable hook means including one member mounted adjacent the edge of said door remote from said first hinge axis and one member mounted adjacent the corresponding edge of said door frame, the relative positions of the said two members being such that with the two door parts set for maximum depth the two members are disengaged from each other whilst with the two door parts set to a lesser depth the two members engage each other to prevent opening movement of the door.
A preferred door assembly according to the present invention is illustrated in the accompanying drawings, in a fuselage of a pressurised aircraft.
In these drawings:
FIG. 1 is a perspective view of an aircraft fuselage with a door in an open position.
FIG. 2 is a sectional elevation taken on line H-IIII of FIG. 1, and FIGS. 3 and 4 are similar sectional elevation but with the door in other positions.
FIG. 5 is a diagrammatic layout of a hydraulic sequencing system shown in the door fully open position.
FIG. 6 is a perspective view of an aircraft in flight showing the general position of the door.
Referring to the figures generally, an aircraft fuselage 10 has a rectangular door frame 11 in its lower side giving access to a freight hold 12 located under the cabin floor 13. The hold 12 itself has a floor 14.
A rectangular door 15 is connected at its upper edge 'ice to the upper edge of the frame by means of a hinge 16, the axis 17 of the hinge, the first hinge axis, lying generally parallel to the longitudinal axis 18 of the fuselage (FIG. 1). The door 15 opens upwards and outwards, the opening (and closing) movements being effected by means of a jack 19 (see FIGS. 2 and 3), a crank 20 mounted on a rotatable tube 21 extending the full width of the door aperture, and spaced cranks 22 on each end of the tube each coupled to push-pull rods 23 which are in turn pivoted to the top edge of the door.
The door 15 is formed of two parts 15a and 15b both of about the same size, and pivoted to each other by means of a hinge 24 whose axis 25, the second hinge axis (FIG. 1) moves as the door pivots about the hinge 16 but remains parallel to the axis 17.
Jacks 26 mounted adjacent the hinge 24 on both parts 15a and 15b of the door control the relative pivotal movement between the parts 15a and 15b.
The periphery of the door 15 is provided with an inflatable seal 33 which deforms on contact with the door frame 11 to give an air tight seal. The centre hinge 24 is provided with a sealing strip 34 which distorts slightly during operation of the jacks 26.
The free edge 27 of the door 15 is provided with hooks 28 which have their mouths directed along the plane of the door towards the hinges 16 and 24. Rods 29 are provided on the bottom edge 30 of the frame and are positioned to lie parallel to the hinge axes in order to be engaged by the hooks 28 on closure of the door 15.
The two parts 15a and 15b of the door are of curved shape in cross-section such that in one relative position they lie with their exterior surfaces in continuous convex relationship with one another, and when the door is fully closed, with the fuselage contour. This condition is shown in FIG. 3. The two parts 15a and 15b can be relatively pivoted one to the other about hinge 24 by means of jacks 26, extension of which moves the parts 15a and 15b from the continuous convex relationship into a dis continuous at least partly concave relationship indicated in FIGS. 1, 2 and 4. In this latter condition, the effective depth of the door, that is, from the hinge 16 to the hooks 28 is increased from that when the parts 15a and 15b are in the continuous convex relationship. This is due to the curvature of the door 15 as a whole unit in this condition; the door 15 is, in effect, tending to be flattened.
Thus extension of the jacks 26 when the door is fully closed disengages the hooks from the rods 29. This is shown in FIG. 4. Contraction of the jacks 26 when the door is closed sufiiciently for the hooks 28 to initially engage the rods 29 causes the effective length of the door 15 to be shortened and thus causes the hooks 28 to fully engage the rods 29.
The jacks 26 are provided with internal locks to hold the door parts in their continuous convex relationship and thereby to maintain the door securely closed. In this condition, pressurisation loads tend to cause the door parts 15a and 15b to pivot about hinge 24 and assume a more convex relationship. This is prevented by the close engagement of the hooks 28 with the rods 29'.
The jacks 26 are also provided with further internal locks to hook the door parts 15a and 15b in their discontinuous, partly flattened, relationship when open. This enables the door 15 to swing clear of the aperture 11, as shown in FIG. 2, with less pivotal movement about hinge 16 than would be necessary if the door remained in its more curved configuration.
Further locking means is provided in case of failure of the internal locks of the jacks 26 or a reversal of the pressurisation loads. The locking means takes the form of shoot bolts 31 (FIG. 1) which are incorporated in the structure of the lower part of the door 15b. The shoot bolts 31 are arranged such that on closure of the door 15 the bolts 31 extend from within the door to engage in sockets 32 in the door frame, thus locking the door firmly.
As an alternative the door 15 can be similarly mounted for inward opening. In this case the two parts 15a and 15b are required to hinge relatively to one another about the second hinge axis 25 to a greater degree than for outward opening so as to clear the door frame 11 and the rods 29 on opening.
A sequencing system (FIG. is provided to ensure that the jacks 19 and 26 operate in the appropriate order during operation of the door 15.
Assuming the door to be in its fully Open position as indicated in FIG. 2 the operational sequence to close the door 15 is as follows:
Fluid pressure from a main hydraulic system line 35 is directed through a cockpit isolating valve 36 to flow to a two position selector valve 37 which in this instance is turned to the close position. Fluid flows from the valve 37 into a supply line 38 which is connected by a supply line 39 to the top of the jack 19. Fluid also flows through the supply line 38 to the first of a pair of sequencing valves 40 and 41 which are connected by a line 42 to each other in series. These valves 40 and 41 delay the flow of fluid to the jacks 26 while fluid entering the top of the jack 19 first unlocks then extends and finally re-locks the jack 19 in a position shown in FIG. 4. The door 15 has now been swung bodily downwards about the hinge 16. Fluid is now allowed to flow from the second sequencing valve 41 via a supply line 43 to the jacks 26 which first unlock then retract and finally re-lock in a position shown in FIG. 3. The parts 15a and 15b of the door have now been pivoted about the hinge 24 to be in continuous convex relationship with each other and with the fuselage contour. The hooks 28 are in full engagement with the rods 29 to hold the door 15 firmly closed.
Fluid leaving the bottom of the jack 19, the tops of the jacks 26, and the bottoms of the sequencing valves 40 and 41 is returned to the hydraulic system return line 44 by return lines 45, 46 and 47.
Opening of the door is achieved in an exactly opposite sequence except that the sequencing valves 40 and 41 are not used since the door 15 cannot move until the jacks 26 have been extended. The valve 37 is turned to open and the return lines 46 and 47 become supply lines 38, 39, 42 and 43 becoming return lines.
4 I claim: 1. A door assembly including in combination, a door frame, a door to fit said frame, first hinge means pivotally connecting one edge of said door to one edge of said frame for pivotal movement relative thereto about a first hinge axis, said door being formed of two parts, and
second hinge means pivotally connecting said two parts for pivotal movement relative thereto about a second hinge axis parallel to said first hinge axis, actuating means efiective with said door in the closed position, for causing limited relative movement of said two parts about said second hinge axis in a sense to vary the eifective depth of said door, engageable hook means including one member mounted adjacent the edge of said door remote from said first hinge axis and one member mounted adjacent the corresponding edge of said door frame, the relative positions of the two members being such that with the two door parts set for maximum depth the two members are disengaged from each other whilst with the two door parts set to a lesser depth the two members engage each other to prevent opening movement of the door.
2. A door assembly according to claim 1 wherein said actuating means comprises at least one hydraulic jack operatively interconnecting said two door parts.
3. A door assembly according to claim 1 wherein a hydraulic sequencing system is provided which includes, two sequencing valves connected in series for delaying actuation of the hydraulic jack operatively interconnecting said two door parts whilst a main hydraulic door jack is operated to close said door.
References Cited UNITED STATES PATENTS 2,689,766 9/1954 Blackman 4940 2,748,855 6/ 1956 Siems et al. 244129 D 2,748,856 6/ 1956- Tatter -210 2,857,874 10/ 1958 McBride, Jr. 114-202 2,993,730 7/ 1961 Weiertz 296146 3,424,41 l 1/1969 Blunschi, Sr., et al. 244-118 R 3,430,382 3/1969 Metz 244-129 D PETER M. CAUN, Primary Examiner us. c1. X.R.