GB2169345A

GB2169345A - Door operating mechanism

Info

Publication number: GB2169345A
Application number: GB8500425A
Authority: GB
Inventors: David Colin Townend
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-01-08
Filing date: 1985-01-08
Publication date: 1986-07-09
Also published as: GB2169345B; GB8500425D0

Abstract

A door operating mechanism for a door having upper and lower leaves which fold about an axis (40) between them, the mechanism comprising a primary joint (20) disposed at the lower end of a primary arm (22) having a fixed upper pivot, arms (30, 32) articulated between the primary joint and the respective door leaves, driving arms (34, 34A) articulated at one end to the primary joint and at the other end to members (36, 36A) movably attached to the upper leaf. Members 36, 36A may be threaded on a rod (40) so that the door can be opened with a folding and lifting action on rotation of the rod. <IMAGE>

Description

SPECIFICATION Door operating mechanism This invention relates to an operating mechanism for a door of the kind having upper and lower leaves which fold about a laterally extending, commonly horizontal hinge and for convenience referred to as such hereinafter, towards one another out of a closed position common plane when the door is lifted for opening.

Doors of the aforementioned kind are commonly used, for example, on aircraft hangars and are often power operated. Known drive systems commonly comprise motors which drive chain and pulley arrangements.

It is an object of this invention to provide an improved operating mechanism for a door of the aforementioned kind.

According to the invention, there is provided an operating mechanism for a door of the kind described, comprising a primary pivot joint located in spaced relationship to the door, a primary arm having a fixed upper pivot and a lower pivot at the primary joint, at least one connecting arm articulated between the primary joint and the upper door leaf, at least one connecting arm articulated between the primary joint and the lower door leaf, two symmetrically arranged driving arms each having a pivot at the primary joint and a pivot at a member connected to and movable generally horizontally across the upper door leaf, said two members being movable in synchronism towards or away from one another, and driving means for the driving arms, the arrangement being such that when the driving means is operated the driving arms are equally and oppositely angularly displaced in a common generally horizontal plane in order either to open the door with folding of the door leaves as the door lifts or to close the door with unfolding of the door leaves as the door lowers.

The driving means may take various forms, but in one arrangement comprises a shaft means with oppositely-handed screwthreaded parts, and a pair of screwthreaded followers, to which the respective driving arms are pivotally connected, respectively movable in opposite directions on the shaft means when the latter is rotated, for example by a driving cog which may itself be chain driven by an electric motor.

The shaft is mounted to the upper leaf of the door, preferably adjacent the horizontal door hinge. However it is preferred not to utilise the shaft mountings for the transmission of forces to the door. Thus, the threaded followers are preferably formed with bearing surfaces in contact with and running along bearing bars provided on the door, whereby forces are transmitted from the driving arms directly through said followers to the bearing bars on the door, and the screwthreaded shaft is not required to take up the load of these forces.

Preferably, the primary pivot joint is located at a level generally corresponding to the level of the horizontal door hinge, and the arrangement is such that it remains generally at the level of said hinge throughout the range of opening and closing (folding and unfolding) movement of the door.

The fixed upper pivot of the primary shaft may be located generally adjacent the upper edge of the upper leaf of the door, but is most preferably located a given distance below said upper edge, the level of said edge being generally unchanging during door opening and closing.

In practice, the door will swing open outwardly from the hangar or other building to which it is mounted, in which case the fixed upper pivot for the primary arm may be carried by a support depending from the roof on the interior of the building.

The position of the fixed upper pivot relative to the closed position common plane of the upper and lower leaves of the door may advantageously be chosen so that "kick-in" of the lower edge of the door is minimised, i.e.

so that this lower edge lifts immediately the door opening movement is commenced (and vice versa on closure), with a minimum component of movement in the horizontal direction. Preferably, therefore, the fixed upper pivot is located generally above the primary joint in the door closed position, so that in said door closed position the primary arm extends substantially or near vertically. It is clearly not convenient to lower the fixed upper pivot of the primary arm below a certain level, but up to this level the lowering of this fixed upper pivot also assists in reduction of "kick in".

The connecting arms extending between the primary joint and the upper and lower leaves are preferably pivotally connected to the respective leaves at intermediate positions between the upper and lower edges of said respective leaves, typically about one third of the distance up the upper leaf from the door hinge and about one third of the distance down the lower leaf from said hinge. A single such connecting arm may suffice for the upper leaf; two symmetrically arranged such connecting arms, disposed in adjacent parallel relationship, are preferred for the lower leaf.

The lower leaf connecting arm(s) fold towards the upper leaf connecting arm(s) as the door is opened (raised and folded), the upper leaf connecting arm(s) in turn folding towards the primary arm. During such door opening movement, the upper leaf is pivotted outwardly to reach a near horizontal position when the door is fully open, and the lower leaf is oppositely pivoted inwardly, to extend beneath the upper leaf also in a near horizontal position in the fully open position. Thus, in this last mentioned fully open position, the upper and lower leaves define a narrow angled V, the bisecting plane of which is substantially horizontal or is inclined at a small angle to the horizontal, with the primary arm lying substantially in said bisecting plane.

Between the fully closed and fully open positions, the driving arms preferably close together from a large included angle typically of about 150 degrees to a small included angle typically of about 30 degrees. This has the advantage that, given a constant output driving means, the actual driving force imparted to the door increases with increase in the stage of opening, so that a maximum driving force is imparted towards the end of the opening movement, which is when the load requirement is greatest. More specifically, the system can be arranged so that during opening and closing (raising and lowering of the door) the imparted driving force at least approximately matches the load requirement throughout the range of movement, even though a prime mover (motor) giving a uniform power output drive is employed.

The primary joint in the preferred arrangement is a complex joint at which six arms, namely the primary arm, the upper leaf connecting arm, the two lower leaf connecting arms and the two driving arms are articulated, the first four about a common horizontal axis and the two driving arms each about a vertical axis. A preferred construction of this primary joint comprises a pivot shaft with squared ends, with the primary arm and upper leaf connecting arm turning at the central region of the shaft, the two lower leaf connecting arms pivoting respectively on opposite sides of the central region, and the two driving arms pivoting on respective pivot pins passing through the respective squared ends of the pivot shaft.

Practical embodiments of door operating mechanism in accordance with the invention are described with reference to the accompanying drawings, in which: Figure 1 is an end elevational view of an aircraft hangar door and operating mechanism therefor; Figure 2 is an isometric view of the operating mechanism; Figure 3 shows detail of a primary hinge; Figure 4 shows a modified system in end elevation; and Figure 5 is a horizontal cross-sectional view on the line A-A of Figure 4.

Referring first to Figures 1 and 2, the reference 10 generally denotes an aircraft hangar door comprising an upper leaf 12 hinged about a horizontal axis 14 to a lower leaf 16.

The door 10 is shown closed in thick solid line, and open in thinner solid line. The door 10 opens outwardly from the mouth of the hangar, and the reference 18 denotes the hangar roof which provides a mounting for the door.

The operating mechanism of this invention is adapted to open and close the door, folding the upper and lower leaves 12 and 16 together as the door is lifted for opening and unfolding the leaves apart as the door is lowered for closing. In the fully closed position, the leaves 12 and 16 lie in a vertical common plane.

The operating mechanism comprises a primary joint 20 spaced from the door on the interior thereof, the primary joint 20 being disposed at the lower end of a primary arm 22 the upper end of which is pivoted at 24 to a support 26 depending from the roof 18. It is to be observed from Figure 1 that the fixed upper pivot 24 of the primary arm 22 is disposed vertically above the primary joint 20, and is also disposed a certain distance below the upper edge 28 of the door. These features minimise "kickin at the closed position of the door, i.e. ensure that the bottom edge 29 of the door has a substantially vertical movement, with a minimum component of movement in the horizontal direction, as it enters or leaves the fully closed position in which it is disposed against or very close to the ground, e.g. to seal thereagainst by means of a suitable sealing strip.

The primary arm 22 has upper and lower horizontal pivot axes, and the lower axis at the primary joint 20 is also the horizontal pivot axis for a connecting arm 30 articulated to the upper leaf 12 and for a pair of adjacent, parallel connecting arms 32, 32A articulated to the lower leaf 16 (see Figure 2). It is to be noted that the drawings actually show part of the fixed framework of the upper and lower leaves of the door 10, the covering skin being omitted.

Also articulated at the primary joint 20, but about vertical pivot axes, are two driving arms 34, 34A which extend laterally in symmetrical relationship, thereby to form a wide angled Vshape, and pivotally connect through vertical pivots with respective members 36, 36A attached to the upper leaf of the door.

The members 36, 36A are constituted by screwthreaded followers which are movable towards or away from one another on a horizontal shaft 40 with oppositely handed screwthreaded parts and carried by the upper leaf of the door just above the horizontal hinge 14. The shaft 40 is drivable in rotation, as by a chain driven cog motored from a suitable motor, thereby symmetrically to cause the driving arms 34, 34A to move angularly towards or apart from one another, thereby to alter the angle between them.

In the closed position of the door 10, the driving arms 34, 34A are disposed in V-relationship enclosing a maximum angle. As the door is opened the driving arms close together eventually to assume a V-relationship with a near zero or minimum angle between them.

In the fully closed position of the door 10, the primary joint 20 is effectively locked in position, as is the door itself. Thus, at the beginning of a door opening drive, the force applied to the driving arms 34, 34A is applied as a reaction, to the upper leaf 12 of the door, thus causing it to start to swing outwardly. The lower leaf 16, due to the restraint imposed by the connecting arms 32, 32A, is thereby caused to lift and then commence to swing inwardly relatively to the horizontal hinge 14.

The operating force of the driving arms 34, 34A is not transmitted to the door 10 through the shaft 40, but is transmitted from the followers 36, 36A directly to a shaped bearing bar 42 carried by the upper leaf 12.

Thus, the outer surface of each follower 36 or 36A constitutes a bearing surface cooperating with and sliding along the bearing bar 42.

In the fully open position of the door 10, shown in thinner lines, the door is also effectively locked in position, in analogous manner to the condition previously described with reference to the fully closed position.

It is to be seen that, in the fully open position, the lower leaf 16 is folded towards the connecting arms 32, 32A in turn folded towards the connecting arm 30 in turn folded towards the upper leaf 12, the upper and lower leaves having a small angle between them produced by the inwardly pivoted position of the lower leaf 16 beneath the outwardly pivoted position of the upper leaf 12.

The primary arm 22 is disposed substantially in the inclined bisecting plane between the two leaves.

The operating mechanism has the advantage that the driving force imparted by the driving arms 34, 34A can be substantially matched to the load requirement, giving a maximum driving force towards the end of the door opening movement.

Detail of the primary joint is shown in Figure 3. It comprises a horizontal pivot shaft 50 with squared ends 52. The primary arm 22 and connecting arm 30 connect at the central region of the shaft, and the connecting arms 32, 32A outside said central region on opposite sides thereof. The driving arms 34, 34A connect with vertical pivot pins 54 passing through the squared ends 52.

Figures 4 and 5 show a modification, generally less preferred, in which the primary arm 22 is inclined in the closed position of the door 10, the latter assuming a substantially horizontal position when fully open. The same references are employed in Figures 4 and 5 as in Figures 1 to 3. Additionally, however, Figure 5 shows the driving cog 60 for the screwthreaded shaft 40 and mounting brackets 62 for said shaft. It should also be mentioned that, if desired, limit stops may be provided on the shaft 40.

It is to be understood that the above-described embodiments are by way of example only and may be modified in various ways within the scope of the invention hereinbefore described. In particular, it is to be emphasised that the illustrated means for driving the driving arms 34, 34A, namely the screwthreaded shaft and its followers, may be replaced by an hydraulic drive or any other convenient drive which acts, via said arms, through connections which allow the ends of the arms to move laterally of the door and transmit a driving force thereto.

Moreover, it should be made clear that the lateral door hinge, about which the door leaves fold, may be inclined so as to lie parallel with the sloping ridge line of a roof, so that where a pair of folding doors are employed to close the entrance to a building such as an aircraft hangar, the folding doors of the pair respectively have oppositely inclined lateral hinges, and the door leaves assume appropriate quadrilateral shapes to enable complete closure whilst also enabling complete opening of the entrance right up to the ridge apex.

Finally, in addition to the possibility of employing a plurality of connecting arms, possibly arranged in a V-shape, between the primary joint and the respective door leaves, it will sometimes be convenient, in order to increase rigidity, to employ either a Y-shaped primary arm or possibly two separate primary arms, extending from the primary joint up to a pair of spaced but aligned fixed pivots carried below the building roof.

Claims

1. An operating mechanism for a door of the kind having first and second leaves which fold towards one another about an elongate hinge between them when the door is opened, the operating mechanism comprising a primary pivot joint located in spaced relationship to the door, a primary arm having a fixed first pivot and a second pivot at the primary joint, at least one connecting arm articulated between the primary joint and the first door leaf, at least one connecting arm articulated between the primary joint and the second door leaf, two symmetrically arranged driving arms each having a pivot at the primary joint and a pivot at a member connected to and movable relative to the one door leaf, said two members being movable in synchronism towards or away from one another, and driving means for the driving arms, the arrangement being such that when the driving means is operated the driving arms are equally and oppositely angularly displaced in a common plane for opening of the door by folding the leaves or closing the door by unfolding the leaves.

2. An operating mechanism for a door of the kind hereinbefore described, the operating mechanism comprising a primary pivot joint located in spaced relationship to the door, a primary arm having a fixed upper pivot and a lower pivot at the primary joint, at least one connecting arm articulated between the primary joint and the upper door leaf, at least one connecting arm articulated between the primary joint and the lower door leaf, two symmetrically arranged driving arms each having a pivot at the primary joint and a pivot at a member connected to and movable generally horizontally across the upper door leaf, said two members being movable in synchronism towards or away from one another, and driving means for the driving arms, the arrangement being such that when the driving means is operated the driving arms are equally and oppositely angularly displaced in a common generally horizontal plane in order either to open the door with folding of the door leaves as the door lifts or to close the door with unfolding of the door leaves as the door lowers.

3. A mechanism according to claim 1 or claim 2, wherein the driving means comprises a shaft means with oppositely-handed screwthreaded parts, and a pair of screwthreaded followers, to which the respective driving arms are pivotally connected, respectively movable in opposite directions on the shaft means when the latter is rotated.

4. A mechanism according to claim 3, wherein the shaft means is drivable by a driving cog itself drivable by an electric motor.

5. A mechanism according to claim 3 or claim 4 when appendant to claim 2, wherein the shaft is mounted to the upper leaf adjacent the horizontal door hinge.

6. A mechanism according to claim 5, wherein the threaded followers are formed with bearing surfaces in contact with and running along bearing bars provided on the door, whereby forces are transmitted from the driving arms directly through said followers to the bearing bars on the door, and the screwthreaded shaft is not required to take up the load of these forces.

7. A mechanism according to claim 2 or any claim appendant thereto, wherein the primary pivot joint is located at a level generally corresponding to the level of the horizontal door hinge, and the arrangement is such that it remains generally at the level of said hinge throughout the range of opening and closing (folding and unfolding) movement of the door.

8. A mechanism according to claim 7, wherein the fixed upper pivot of the primary shaft is located adjacent to but below the upper edge of the door, the level of said edge being generally unchanging during door opening and closing.

9. A mechanism according to claim 8, wherein the fixed upper pivot for the primary arm is carried by a support depending from the roof on the interior of the building closable by the door.

10. A mechanism according to claim 8 or claim 9, wherein the position of the fixed upper pivot relative to the closed position common plane of the door leaves is selected so that the lower edge of the door lifts immediately the door opening movement is commenced (and vice versa on closure), with a minimum component of movement in the horizontal direction.

11. A mechanism according to claim 10, wherein the fixed upper pivot is located generally above the primary joint in the door closed position, so that in said door closed position the primary arm extends substantially or near vertically.

12. A mechanism according to claim 2 or any claim appendant thereto, wherein the primary joint and the upper and lower leaves are pivotally connected to the respective leaves at intermediate positions between the upper and lower edges of said respective leaves, typically about one third of the distance up the upper leaf from the door hinge and about one third of the distance down the lower leaf from said hinge.

13. A mechanism according to claim 2 or any claim appendant thereto, wherein, between the open and closed positions, the driving arms close together from a large included angle typically of about 150 degrees to a small included angle typically of about 30 degrees.

14. A mechanism according to claim 2 or any claim appendant thereto, having a single upper leaf connecting arm and two symmetrically arranged, parallel connecting arms for the lower leaf.

15. A mechanism according to claim 14, wherein the primary joint is a complex joint at which six arms, namely the primary arm, the upper leaf connecting arm, the two lower leaf connecting arms and the two driving arms are articulated, the first four about a common horizontal axis and the two driving arms each about a vertical axis.

16. A mechanism according to claim 15, wherein the primary joint comprises a pivot shaft with squared ends, with the primary arm and upper leaf connecting arm turning at the central region of the shaft, the two lower leaf connecting arms pivoting respectively on opposite sides of the central region, and the two driving arms pivoting on respective pivot pins passing through the respective squared ends of the pivot shaft.

17. A door operating mechanism substantially as hereinbefore described with reference to the accompanying drawings.