GB2165877A - Folding door for buses - Google Patents

Abstract

In a folding door for buses, two panels (2,3) are hinged together along adjoining edges (17,18). In correspondence with these edges (17,18), the door has a device for preventing the undesired opening up of the closed panels, which comprises a groove (21) rigid with one (2) of the panels and a rib (22) rigid with the other panel (3). When the panels (2,3) are closed, the rib (22) is engaged in the groove (21) to prevent the panels from being deformed and opened up by accidental pushing against them. <IMAGE>

Description

SPECIFICATION Folding door for buses and the like The present invention relates to a folding door for buses and the like, of the type in which two panels are hinged together along adjoining edges, and which includes a device for preventing the undesired opening up of the closed panels.

Folding doors are particularly widely used in buses intended for urban and suburban transport, because of their simplicity and low cost.

As is known folding doors, which in themselves are capable of being used with both inward and outward opening, are in practice only used so as to open inwardly at present; this is because of safety regulations which, in the case of outwardly opening doors, prescribe the use of complicated and expensive locking systems for preventing accidental opening in the event of outward pushing by the passengers.

If the door opens inwardly, however, there is no risk of pushing by the passengers being able to open it.

However, the pushing may cause resilient bending of the door panels. If the panels are hinged to each other by two simple hinges, one at the bottom and one at the top, it is easy for the bending of the panels to lead to the parting of the edges which are hinged together. This damages the door, since continuous and repeated bending causes permanent deformation of the panels with consequent difficulty in the opening and closing movements.

In addition, there is the possibility of accidents to the passengers. Indeed, if anyone inadvertently put part of his body (for example a finger) between the panels bent by the pushing of the passengers, he would certainly be injured when the pushing stops.

Thus, the problem exists of constructing a bus door which can withstand pushing from the interior without risk of the passengers and without mechanical damage.

In order to resolve this problem, a device is needed to prevent the undesired opening up of the closed panels.

According to the most widely used prior art, attempts have been made to solve this problem by the use of a continuous hinge extending over the entire height of the door, instead of separate hinges. In this way, any opening up of the panels is prevented and the cause of risk to the passengers is thus eliminated. Mechanical damage due to deformation is also avoided since there is no possibility of the panels parting.

Continuous hinges, on the other hand, are more expensive than simple hinges and, in particular, are more prone to wear. Moreover, they vibrate easily and are thus sources of irritating noise.

The object of the present invention, therefore, is to resolve the problem explained above, that is, to provide a bus door which can withstand pushing from the interior, while avoiding the disadvantages of continuous hinges.

This object is achieved, in accordance with the present invention, by a door of the aforesaid type, wherein the device for preventing the undesired opening up of the closed panels comprises, in correspondence with the adjoining edges, a groove rigid with one of the panels and a rib rigid with the other panel, which is engaged in the groove when the panels are closed.

Further characteristics and advantages of a bus door according to the invention will become more apparent from the following description of a preferred embodiment, given, by way of example, with reference to the appended drawings. In the drawings: Figure 1 is a view of a door according to the invention, with the panels closed; Figure 2 is a panel of a detail of the door of Figure 1, taken on the line ll-ll; Figure 3 is a panel corresponding to Figure 2 during the opening of the panels.

In the drawings, a door of a bus A (only illustrated schematically in the drawings) is generally indicated 1; the door 1 is of the four-panel folding type, with two side panels 2 and two central panels 3.

The panels 2 and 3 have essentially identical structures and comprise respective rectangular frames 4 and 5 within which respective panes of glass 6 and 7 are mounted with the interposition of sealing strips 8 and 9.

The side panels 2 have upper driving pins 10 fixed to the frames 4 close to their outer edges 11 and rotatable by pneumatic means (not illustrated).

The panels 2 are also provided with lower idle pins 12 fixed to the respective frames 4 close to the edges 11 and in alignment with the driving pins 10.

Each central panel 3, however, is provided with an upper pin 13 fixed to the frame 5 close to its outer edge 14; the pin 13 is slidable in a guide, only shown schematically and indicated 15. The edge 14 is provided with a rubber profile 16 to improve the sealing of the door 1.

Each panel 2 is hinged to the adjacent panel 3 along respective adjoining edges 17 and 18 by two hinges 19 and 20 of the type with anti-friction bearings (not illustrated). The hinges 19 and 20 have hinge axes outside the door 1 with respect to the bus A, to allow the door 1 to open inwardly.

In correspondence with the edges 17 and 18, the door 1 has a device for preventing the undesired opening up of the closed panels. This device comprises a groove 21 rigid with one of the panels and a rib rigid with the other panel. More particularly, the groove 21 is substantially trapezoidal and is formed along the edge 17 of the panel 2, while the rib is constituted by a plurality of spaced-apart wedges 22 carried by the edge 18 and intended for insertion in the groove 21 during closure of the door. The wedges 22 are formed of synthetic plastics material and have panels which substantially mate with the profile of the groove 21, with a wide bevel to facilitate insertion.

To advantage, the wedges 22 have a mounting tongue 23 which is substantially T-shaped so that they are fixed in a T-shaped groove 24 formed along the edge 18 of the panel 3. For the sole pur pose of standardising the parts, the groove 24 and the groove 21 illustrated have the same panel, with a front portion which is substantially trapezoidal and a rear panel which is T-shaped.

Two further grooves 25 and 26 are formed along the edges 17 and 18 alongside the grooves 21 and 24, for housing a substantially U-shaped cover 27 formed of flexible material so that it can follow the movements of the panels 2 and 3 during opening and closing of the door.

The operation of the door 1 described will now be explained with particular reference to Figures 2 and 3.

Figure 2 shows the closed-door condition. In this condition, the wedges 22 are engaged in the groove 21 so as to interconnect the panels 2 and 3.

Upon opening of the door 1, the side panels 2 are rotated about their respective pins 10 and 12 and pull the central panels 3 hinged thereto and guided by the pins 13 in the guide 15. Thus, the typical folding movement is achieved by which each central panel 3 is folded against the side panel 2.

During this movement, the panels 2 and 3 move angularly relative to each other about the hinges 19 and 20, as shown in Figures 2 and 3. The wedges 22 are no obstacle since they are disengaged from the groove 21. During the opposite closing movement, the wedges 22 fit into the groove 21 again, to restore the interconnection.

As will be appreciated, the door according to the invention solves the technical problem explained at the beginning of the description. In fact, no amount of pushing from the inside can cause the panels to part since they are interconnected by the wedges; on the contrary, pushing from the interior causes an even greater forcing of the wedges into the groove. Thus, any risk of accident to the passengers or damage to the door itself is avoided.

The solution to the aforesaid problem afforded by the present invention, however, does not have the disadvantages typical of continuous hinges; in fact there are no parts which can start vibrating to cause irritating noises and no parts subject to considerable wear since the only two hinges are provided with anti-friction bearings. Finally, from the point of view of cost, the door according to the invention is cheaper than one with a continuous hinge, particularly because of the minimum need for maintenance.

Finally, it is clear that a door according to the invention could be used to advantage not only in a bus but also in similar means of public transport means.

Claims (5)

1. A folding door for buses and the like, of the type in which two panels are hinged together along adjoining edges and which includes a device for preventing the undesirable opening up of the closed panels, wherein the device comprises, in correspondence with the edges, a groove formed in one of the panels and a rib rigid with the other panel, which engages the groove when the panels are closed.

2. A door according to Claim 1, wherein the rib is constituted by a plurality of spaced-apart wedges.

3. A door according to Claim 2, wherein the wedges and the groove have substantially trapezoidal sections.

4. A door according to Claim 2 or 3, wherein the wedges are fixed in a further groove formed in the panel.

5. A folding door substantially as herein described with reference to, and as shown in, the accompanying drawings.