EP3569805A1

EP3569805A1 - A system for closing and opening at least one leaf of an inward swinging door

Info

Publication number: EP3569805A1
Application number: EP18382342.6A
Authority: EP
Inventors: Arnau Lloses Sala
Original assignee: Masats SA
Current assignee: Masats SA
Priority date: 2018-05-18
Filing date: 2018-05-18
Publication date: 2019-11-20

Abstract

A system (100) for closing and opening at least one leaf (1) of an inward swinging door, in which
- at one end (6a), one edge (6) of the leaf (1) is guided by a straight guide (3), and
- in one middle section (6b), said edge (6) is connected by an articulated connection around a vertical articulation shaft (E1) to an arm (2) mounted to rotate around a pivot shaft (E3), all acting as a connecting rod-crank mechanism, with the leaf (1) performing the connecting-rod function and the arm (2) the crank function.

The system comprises actuation means (7) of the leaf (1), equipped with an actuator (7a) fixed solidly to one of the leaf (1) or the arm (2), and which applies a moment of force (Mm) on the other of said leaf or arm around the aforementioned articulation shaft (E1).

Description

Technical sector of the invention

The invention discloses a system for closing and opening at least one leaf of a swinging door, especially suitable for inward swinging doors, and more specifically, applicable to doors of passenger transportation vehicles such as buses, trains, etc.

Background of the invention

Different types of mechanisms are currently known for closing and opening the leaf or leaves of a door of passenger transportation vehicles, such as buses, coaches and trains. Examples of these types are sliding doors and inward swinging doors.
Specifically, an inward swinging door is understood as a door whose leaf has a guide device positioned close to its main lateral edge (on two-leaf doors, the one that is oriented towards the side of the other leaf). This guide device, such as a carriage, is forced to move along a fixed track arranged in the direction of the upright of the door opening of the vehicle. A shaft or vertical bar of the door is connected to the top and/or bottom of the door leaf close to its exit side edge (the one opposite the main side edge) by means of a lever arm. When the actuation means, such as an electric motor, make said vertical bar of the door rotate, the exit edge of the door is brought towards the inside of the vehicle, by the effect of the arm, while the guide device forces the main edge to move towards the door jamb in the open position.
In the end open position, the door leaf is positioned essentially perpendicular to the side of the vehicle and as close as possible to the jamb. Thus, when it moves from the closed position to the open position, the corners of the main side edge follow an essentially straight path while the corners of the exit side edge follow an essentially curved path, giving the leaf a compound movement, rotating around a point that follows a curved path.
For example, patent document EP0351877 describes a system for actuating and guiding one or two leaves of inward swinging doors, which comprises a drive arm that rotates around a shaft secured to the vehicle frame and with an articulated connection around a vertical shaft of an upper edge of a leaf of the door, with the movement of the opposing edge of the leaf conditioned by a straight guide.
To this end, a wheel connected by a support arm to the end associated with the upper edge of the leaf slides through the guide. The leaf is therefore able to turn around the support of the wheel in the guide.
One of the primary objectives of the present invention is to provide an alternative to the known systems, exemplified by patent document EP0351877 .
The doors used in passenger transportation vehicles do not vary considerably, but rather comply with a series of standards that are common to most manufacturers. What does vary is the design and the dimensions of the space inside the public transportation vehicle near the housing compartment for the door arranged in the vehicle body.
As shown schematically in Fig. 1 of this application, to minimize the space occupied by this type of system inside the vehicle, an ideal solution would be to position the guide 3 below the lintel 11 (illustrated with dashed lines) of the housing compartment for the door that is arranged in the vehicle body.
However, if the door leaf 1 also must be oriented perpendicular to the lintel 11 in the open position, which is the exact situation shown in Fig. 1, the alignment L between the articulated connection E1 of the arm 2 with the leaf 1 and the support E2 of the wheel 4 in the guide 3 is perpendicular to said guide.
The drawback of this geometric arrangement is that when the door is in the open position, the rotation of the arm 2 is blocked in the direction that allows the door to close. Indeed, the torque Mm transmitted on the first end 2a of the arm 2 to initiate the movement to close the leaf 1 from the door-open position generates a reaction torque Mr on the second end 2b of the arm 2 in the direction opposite the direction of closing, which generates an opposing force Fop on the support E2 in the direction opposite the door-closing direction, with the wheel 4 therefore stopped motionless in the end stop of the guide 3.
To prevent this problem of the blocking of the leaf 1 in the door-open position, an eccentricity "e" must be produced between the support E2 and the articulation shaft E1 of the leaf 1 with the arm 2, as shown schematically in Fig. 2.
To implement this eccentricity, the support arm 13 that connects the leaf 1 with the support E2 must be longer and is unavoidably forced to position the guide 3 in a position shifted a predetermined distance "d" towards the inside of the vehicle, in other words displaced out of the vertical plane of the lintel 11, as shown in figure 2, if the leaf 1 is to remain positioned under the lintel 11 in the closed-door position, as shown in Fig. 4.
The proposal according to patent document EP0351877 shows that the guide is in effect shifted inward in the vehicle compartment to overcome the eccentricity established between the support of the leaf in the guide and the articulated connection of the leaf with the drive arm.
In some cases, the doors may be installed after the vehicle is manufactured, or the systems installed at the factory may be replaced or substituted. Moving the guide towards the inside of the vehicle may present some drawbacks related to the available space because there may be mechanical interference with other components of the vehicle or the frame.
Another objective of this invention is to provide a system that overcomes these drawbacks.
It is desirable for said system to also be simple in terms of construction, and compact, which is to say, for example, that it requires minimal space inside the vehicle.
It is also interesting for the system to be compatible with solutions that allow the door to be safely interlocked in the closed position, to prevent the door from being forced manually in the direction of opening from inside or outside the vehicle.

Description of the invention

In order to provide a solution to the problems proposed, the invention discloses a system for closing and opening at least one leaf of an inward swinging door with respect to a frame, said leaf having a main side edge, an exit side edge, and respective top edge and bottom edge, in which

at one end near the main side edge, one edge of the leaf is guided by a straight guide, secured to the frame and essentially horizontal; and
in one middle section, the same edge is connected by an articulated connection around a vertical articulation shaft to an arm mounted to rotate around a pivot shaft, secured to the frame and essentially vertical, all acting as a connecting rod-crank mechanism, with the door leaf performing the connecting-rod function and the arm the crank function;

The system according to the invention is separated from the solutions in which the arm is the drive component of the system. In the system according to the invention, a moment of force applied directly around the articulated shaft around which the leaf is articulated to the arm guarantees the movement of the leaf, even when the geometric arrangement of the nodes of the system is not favourable to allow this, if the drive component is the arm.
The system therefore allows its essential components to be arranged advantageously with respect to other similar systems.
Therefore, in a variant of interest, the first end of the edge of the leaf is connected by an articulated connection around a shaft pulled along the length of the straight guide during the maneuvers to open and close the leaf between the end door-closed and door-open positions, and in the door-open position, the aforementioned pulled shaft and the vertical articulation shaft between the leaf and the arm are aligned along an imaginary line that is essentially perpendicular to the straight guide.
According to one embodiment, in the door-closed position, the aforementioned pulled shaft and the vertical articulation shaft between the leaf and the arm are both on the vertical projection of the straight guide.
The system according to the invention prevents the leaf from becoming blocked in its door-open position, even though the articulation shaft and pulled shaft are aligned parallel with respect to the plane of the leaf, in other words, without the need to create an eccentricity between the two articulation shafts, as would happen in the known systems.
Also, since said eccentricity is not required, it is possible to significantly reduce the backward movement of the leaf that is generated when the leaf has reached a position close to the closed position, at which point the articulation shaft is aligned with the pulled shaft and with the pivot shaft of the arm along an imaginary line, such that when the articulation shaft moves beyond this position with the aligned shafts, in one direction of its rotation or the other, said backward movement of the leaf occurs.
Indeed, when said eccentricity is not created, the geometric arrangement of the articulation shafts favours the decrease of the backward movement of the leaf, because the angular distance that the articulation shaft of the arm must travel from the aforementioned position with the shafts aligned until it reaches its end closed position, and vice-versa, is significantly less than the distance required in the known systems that use said eccentricity.
Taking advantage of the features of the system, in a variant, the straight guide is positioned below the lintel of the housing compartment for the door arranged in the vehicle frame, the guide consequently being essentially coplanar to the door leaf when said leaf is in the closed position.
The positioning of the straight guide below the lintel makes it possible to minimize the space occupied in the vehicle. In addition, modifications do not need to be made inside the vehicle, which simplifies its application in different vehicle bodies.
The actuator is intended to be fixed solidly to the leaf or the arm. Also, the actuator is intended to apply the moment of force by thrust, using spindles, pistons, telescoping bars, or other mechanisms to do this. However, in a preferable embodiment, with the actuator being fixed solidly connected to the leaf, the vertical articulation shaft is a drive shaft actuated by the actuator and connected to rotate with the arm.
The fact that the actuator 7a is fixed solidly to the leaf 1 (or alternatively to the arm 2) makes it possible to reduce the space occupied inside the vehicle even more, unlike the known systems, in which the actuator is secured to the frame of the vehicle above the bar 5 fixed solidly to the arm 2 to cause it to rotate.
The actuator may be made up of a motor, such as an electric motor, with an exit drive shaft that can be easily connected to rotate with the articulation shaft, in this case being a driven shaft.
Thus, in a variant of the system, the actuator comprises a drive shaft and a transmission with the articulation shaft between the leaf and the arm, such that the axial rotation of the articulation shaft in one direction or the other, imparted by the drive shaft, modifies the angle formed between the arm and the leaf, whose mechanical connections with the pivot shaft and the guide, respectively, both fixed to the frame, impart a compound movement to the leaf towards its open or closed positions.
According to a first embodiment, with the drive shaft of the actuator being oriented horizontally, the transmission comprises a pair of interconnected gears with perpendicular shafts, arranged such that a first horizontal-shaft gear is solidly connected to rotate with the drive shaft, while a second vertical-shaft gear is solidly connected to rotate with the vertical articulation shaft.
According to another embodiment, with the drive shaft of the actuator being oriented horizontally, the transmission comprises

a first pair of interconnected gears with perpendicular shafts, arranged such that a first horizontal-shaft gear is solidly connected to rotate with the drive shaft, while a second vertical-shaft gear is solidly connected to rotate with a first end of a thrust arm that is positioned at a level above said second gear; said thrust arm in turn being connected by an articulated connection at its other end to a first end of a transmission connecting-rod, and said transmission connecting-rod being connected by an articulated connection at its other end to an eccentric point of a rotating plate; and
a second pair of vertical-shaft gears, with a third and fourth gears interconnected, arranged such that the third gear is solidly connected coaxially to said rotating plate, while the fourth gear is solidly connected to rotate with the vertical articulation shaft of the arm.

This second embodiment is particularly interesting because it offers the possibility of equipping the system with blocking of the door in the closed position to prevent risk situations. Specifically, it is arranged so that when the leaf adopts a position of the door open or partially open, the rotating shaft of the first end of the thrust arm stays on a same first side of the imaginary line that connects the axes of both connecting-rod ends, while when the leaf adopts a position of the door closed, the rotating shaft of the first end of the thrust arm moves to the other side of the aforementioned imaginary line that connects the axes of both connecting-rod ends, producing an auto-interlocking effect of the transmission if an attempt is made to move the leaf in the door-open direction.
According to another aspect of the system, in one variant, the guide is made up of a profile with an open cross-section that forms a slot, and the shaft pulled along the length of the guide is equipped with a wheel that fits inside said slot.
According to a preferred embodiment of the invention, an installation is disclosed for closing and opening the two leaves of a double inward swinging door, specifically for doors of passenger transportation vehicles, which comprises two systems as described above, symmetrically arranged, and one for each leaf, which share a same guide.

Brief description of the drawings

In order to contextualize the invention and the drawbacks related to the state of the art:

Fig. 1 is a schematic plan view of a system for opening and closing a door, in which, exemplifying the state of the art, the arm is the drive component of the system, with the leaf adopting a door-open position, and in which both articulation shafts of the leaf are positioned with no eccentricity between them; and
Fig. 2 is a schematic plan view of another system for opening and closing a door, in which, exemplifying the state of the art, the arm is the drive component of the system, with the leaf also adopting a door-open position, and in which both articulation shafts of the leaf are arranged with a predetermined eccentricity.
In relation to the system proposed by the invention:
Fig. 3 shows a schematic plan view of a system according to the invention, with a geometric arrangement similar to that of the system in Fig. 1, with the difference that the arm is not the drive component;
Fig. 4 is a schematic view of the system according to Fig. 2 to illustrate a backward distance R of the leaf to which the leaf is subjected at the start of the opening maneuver;
Fig. 5 is a schematic plan view of the system according to the invention, to show a shorter backward distance R in the same conditions;
Fig. 6 is a cross-sectional view of the system according to Fig. 5 cut along the cross-sectional plane VI-VI;
Figs. 7a, 7b and 7c show three perspective views of a variant of the system according to the invention seen from the inside of the vehicle, showing part of a door leaf, and that represent the sequence of movement of the system from the closed-door position, passing through an intermediate position, and until it reaches the closed-door position, respectively;
Figs. 8a, 8b and 8c show three perspective views of another variant of the system according to the invention seen from inside the vehicle, showing part of a door leaf, and which represent the sequence of movement of the system from the closed-door position, passing through an intermediate position, and until it reaches a closed-door position, respectively; and
Fig. 9 is a detailed enlarged view of the transmission in the closed-door position of the variant in Figs. 8a to 8c.

Detailed description of the invention

A system 100 according to the invention has been represented according to two preferred embodiments in Figs. 7a to 7c and 8a to 8c, respectively.
These figures show a partial view of a leaf 1 of an inward opening door, showing a sequence of movement of the leaf 1, in the door-closed position (Figs. 7a, 8a), in an intermediate position (Figs. 7b, 8b), and in a door-open position (Figs. 7c, 8c), respectively. On the leaf 1 in the drawings, the main side edge 1a and the exit side edge 1b are partially visible, and the upper edge 6 is fully visible. In the context of the present invention, the expression upper edge is used to designate the upper end or portion of the leaf.
In the case of a two-leaf door, two systems 100 according to the invention will be used, arranged symmetrically, one for each door leaf. Below, for the purposes of clarity, the system 100 of the invention will be described making reference to a leaf, making no distinction as to whether it is part of a single-leaf or double-leaf door.
In the two embodiments mentioned before, the system 100 is arranged as a connecting rod-crank mechanism, with the door leaf 1 performing the connecting-rod function and an arm 2 rotating around a pivot shaft E3, secured to the frame 12, the crank function. Conventionally, the arm 2 is connected at one end 2a to a significantly vertical bar 5 that turns around the pivot shaft E3, whose upper and lower ends are points secured to the frame 12. It should be noted that unlike the known proposals, the rotating arm 2 is not the drive component of this mechanism.
In the examples, the arm 2 is positioned at a level above the upper edge 6 of the leaf 1 and it is articulated at its other end 2b around a vertical articulation shaft E1 to a middle portion 6b of the edge 6. At one end 6a near the main edge 1a of the leaf 1, the same edge 6 of the leaf 1 is connected articulated around a pulled shaft E2 that slides along a straight guide 3, in a back and forth movement during the maneuvers to open and close the door. The guide 3 is essentially horizontal and is positioned at a level immediately above the upper edge 6 of the leaf 1.
The guide 3 is made up of a profile with an open cross-section that forms a slot, in which a wheel 4 or roller is inserted and slides, having a vertical shaft that defines the pulled shaft E2 mentioned before, around which the leaf 1 will be able to turn. Other solutions are intended to give this pulled shaft E2 a sliding movement along the guide 3, which could be carriages, skids, wheels, bearings, slider devices, etc. Although in the examples, a support arm 13 connects the leaf 1 to the pulled shaft E2 because the guide 3 is slightly shifted out of phase with respect to the door lintel 11, the pulled shaft E2 is also intended to be positioned above the vertical projection of the leaf 1 when the guide 3 is positioned in the same vertical projection of the lintel. As explained later, the system 100 of the invention is suitable for placing the guide 3 in this position coinciding with the lintel 11, with this not causing a mechanical interlocking in the situation with the door open.
In the two variants of the system 100, actuation means 7 cause the movement to the leaf 1. Advantageously, said actuation means 7 comprise an actuator 7a fixed solidly to the leaf 1 and which applies a moment of force Mm, or torque, on the arm 2 around the vertical articulation shaft E1. This moment of force Mm, as will be described in greater detail below, modifies the angle formed between the arm 2 and the leaf 1 whose mechanical connections with the pivot shaft E3 and with the guide 3, respectively, both fixed to the frame 12, impart a compound movement to the leaf 1 towards its open or closed positions.
Although it is not shown, this solution is equally valid to mount the actuator 7a solidly to the arm 2, such that a moment of force Mm is applied, in this case to the leaf 1.
Figures 7a and 8a show the closed-door position, wherein the wheel 4 is positioned at one end of the guide 3 (in two-leaf doors, this would correspond to an intermediate point of the guide 3); while figures 7b and 8b show that the wheel 4 has moved to an intermediate position, towards the opposite end of the guide 3 wherein the leaf 1 will reach its door-open position (see figures 7c and 8c).
During the door opening and closing maneuvers, the leaf 1 follows a compound movement, turning around the vertical articulation shaft E1, which in turn rotates around the pivot shaft E3, all while keeping the pulled shaft E2 in the guide 3, and consequently forcing it to follow a straight path.
The system is dimensioned such that when the door leaf 1 is in the door-open position (figures 3, 7c and 8c), the plane of the leaf 1 is oriented perpendicular to the vertical plane of the door lintel 11, or in other words, perpendicular to the guide 3, with the leaf 1 inside the vehicle.
As shown in the schematic view in Fig. 3, which shows the open position, the articulation shaft E1 and the pulled shaft E2 are aligned along the imaginary line L, significantly parallel and adjacent to the upper edge 6 of the leaf 1 and perpendicular to the vertical plane of the guide 3.
In this position, when the actuator 7a applies a moment of force Mm on the arm 2 around the vertical shaft E1 and in the direction indicated by the arrow in Fig. 3, the angle formed between the leaf 1 and the arm 2 will unavoidably tend to open. By reaction of this moment of force, the leaf 1 will transmit thrust to the pulled shaft E2 in the direction of the guide 3, in the direction that moves the pulled shaft E2 towards the closed-door position.
In practice, the moment of force Mm generated is capable of counteracting any opposing force Fop that could block the movement of the wheel 4 at the start of the door-close maneuver.
The system of the invention resolves the drawbacks of the systems known in the state of the art, which are described in greater detail in the background of the invention section. Indeed, because the actuation means 7 of the system of the invention apply a moment of force Mm specifically around the vertical shaft E1 of the articulated connection between the leaf 1 and the arm 2 (see Fig. 3), instead of acting directly on the arm 2 as in the known systems (see Figs. 1 and 2), correct operation is guaranteed during the door-close maneuver, overcoming the mechanical interlocking problems associated with these known systems, all without the need to create an eccentricity "e" between the articulation shaft E1 and the pulled shaft E2, as, we insist, occurs in the known systems (see Fig. 2).
With respect to the aspects described above, unlike the systems known in state of the art (see figure 2), the system 100 allows the guide 3, if desired, to be positioned to coincide with the lintel 11 in the vehicle frame, with the guide 3 being essentially coplanar with the door leaf 1 when said leaf 1 is in the closed-door position (see Figs. 5 and 6).
The positioning of the guide 3 below the lintel 11 makes it possible to minimize the space occupied inside the vehicle and facilitates the installation of a system with these characteristics.
Likewise, the positioning of the actuator 7a fixed solidly to the leaf 1 (or alternatively to the arm 2) makes it possible to reduce the space occupied inside the vehicle even more, unlike the known systems, in which the actuator is secured to the frame of the vehicle above the bar 5 fixed solidly to the arm 2 to cause it to rotate.
Also, since said eccentricity "e" is not required, it is possible to significantly reduce the backward R of the leaf 1 that is generated when the leaf 1 has reached the end closing position.
To explain more clearly said backward effect that is generated in the leaf 1, a system of the state of the art is shown, in which the pulled shaft E2 is positioned with a certain degree of eccentricity "e" with respect to the leaf 1 (see Fig. 4), and a system according to the invention (see Fig. 5) which does not have said eccentricity.
The backward "R" of the leaf 1 in the closed position can be calculated by the equation: $R = (A + B) - C$
where:

"A" is the distance between the articulation shaft E1 and the pulled shaft E2;
"B" is the distance between the articulation shaft E1 and the pivot shaft E3;
"C" is the distance between the articulation shaft E2 and the pivot shaft E3.

The backward of the leaf 1 is generated when the leaf 1 reaches a position close to the closed position, in which the articulation shaft E1 is aligned with the pulled shaft E2 and with the pivot shaft E3 of the arm 2, along an imaginary line, such that when the articulation shaft E1 moves beyond this arrangement with the shafts in alignment, in one direction of its rotation or the other, said backward R is generated in the leaf 1.
In the aligned geometric configuration of the system of the invention (see Fig. 5), in other words, without eccentricity, the backward R of the leaf 1 is less than in the case of the system that uses said eccentricity "e" (see Fig. 4), because the angular distance that the articulation shaft E1 of the arm 2 must travel from the aforementioned position of shafts aligned until it reaches the end closed position, and vice-versa, is significantly shorter than the distance required in the known systems that use said eccentricity (see figure 4).
Scaling the examples shown to an installation with standard dimensions, with the system of the invention, it is obtained a backward of 4.6 mm, while with the system of the state of the art, a backward of 19.9 mm is generated.
A practical solution for applying the moment of force Mm around the articulation shaft E1 is described below.
In essence, this solution is based on making the articulation shaft E1 a rotating, driven shaft, with a rotating connection to the arm 2. This rotating connection is implemented in the examples by means of a cardan joint, which allows it to absorb small movements of the leaf 1 out of a perfectly vertical plane. Likewise, this connection by cardan joint is completed with a fork with the capacity to rotate around the axial axis of the arm 2.
To make the driven vertical shaft E1 rotate around itself, the actuator 7a can be selected in the form of an electric motor with an output shaft, which we will call the drive shaft 8, coupled directly, or by means of a transmission, to the driven vertical shaft E1.
The variants in Figs. 7a to 7c and 8a to 8c show different variants of this transmission, which is necessary when the drive shaft 8 is not aligned axially with the driven articulation shaft E1.
According to a first variant shown in Figs. 7a to 7c, the transmission 9a comprises a pair of interconnected gears 15,16 with perpendicular shafts, arranged such that a first horizontal-shaft gear 15 is solidly connected to rotate with the drive shaft 8 of the actuator 7a, while a second vertical-shaft gear 16 is solidly connected to rotate with the driven vertical shaft E1.
To open the door, from the closed-door position (see Fig. 7a), the rotation of the drive shaft 8 of the actuator 7a is transmitted to the articulation shaft E1 through the pair of gears 15,16, causing the simultaneous rotation of arm 2 and of the leaf 1, closing the angle formed between them.
According to a second variant shown in Figs. 8a to 8c and Fig. 9, the transmission 9b comprises a first pair of interconnected gears with perpendicular shafts, arranged such that a first horizontal-shaft gear 15 is solidly connected to rotate with the drive shaft 8 of the actuator 7a, while a second vertical-shaft gear 16 is solidly connected to rotate with a first end 17a of a thrust arm 17 that is positioned at a level above said second gear 16; with said thrust arm 17 in turn connected by an articulated connection at its other end to a first end 18a of a transmission connecting-rod 18, and with said transmission connecting-rod 18 connected by an articulated connection at its other end 18b to an eccentric point of a rotating plate 19. The transmission 9b is completed by a second pair of vertical-shaft gears, with a third 20 and fourth 21 gears interconnected, arranged such that the third gear 20 is solidly connected coaxially to said rotating plate 19, while the fourth gear 21 is solidly connected to rotate with the articulation shaft E1.
To open the leaf 1, from the closed-door position (see Figs. 8a and 9), the rotation of the drive shaft 8 of the actuator 7a causes the swinging of the thrust arm 17 by means of the first pair of gears 15,16, such that the rotation of the thrust arm 17 imparts the movement of the connecting-rod 18, which in turn causes the simultaneous rotation of the rotating plate 19 and the third gear 20, which in turn produces rotational movement of the fourth gear 21, thus causing the articulation shaft E1 to turn, causing the simultaneous rotation of the arm 2 and the leaf 1, closing the angle formed between them.
As shown in Figs 8a and 9, which show the system in the closed-door position, the length dimensions D3 of the thrust arm 17, radial dimensions R1 and R2 of the fourth and third gears 21 and 20, and the radial distance R3 connecting the end 18b of the connecting-rod 18 can be selected, such that the mechanism 9b adopts an arrangement such that is it capable of performing a function to interlock the door.
Specifically, while the leaf 1 adopts a position with the door open or partially open, the rotating shaft of the first end 17a of the thrust arm 17 stays on a same first side of the imaginary line T that connects the axes of both connecting-rod 18 ends 18a,18b, while when the leaf 1 adopts the position with the door closed, the rotating shaft of the first end 17a of the thrust arm 17 moves to a distance "D2" on the other side of the aforementioned imaginary line T, producing an auto-interlocking effect of the transmission 9b if an attempt is made to move the leaf 1 in the door-open direction.
Fig. 9 shows the respective directions of rotation of the main components of the transmission 9b by means of arrows. As shown, the moment of force M1 applied to the fourth gear 21 when the leaf 1 is to be opened, forcing the system, is transmitted in the direction of rotation M2 to the third gear 20, generating a force F1 on the second end 18b of the connecting-rod 18, which is in turn transmitted to the thrust arm 17. However, thanks to the aforementioned blocking arrangement of unaligned shafts, the connecting-rod 18 cannot be moved in the opening direction, because a moment of force M3 is produced on the first end 17a of the thrust arm 17 in the direction opposite to the opening direction, capable of transmitting an opposing force F2 on the first end 18a of the arm 18 that tends to push the connecting-rod 18 against an end stop 12a secured to a point on the frame of the vehicle, intended to limit the closing movement of the leaf 1 when it reaches said blocking position.
Although said blocking effect may be achieved by having both articulation shafts of the ends 18a and 18b of the connecting-rod 18 aligned with the first end 17a of the thrust arm 17, it is important to note that said surpassed position of the first end 18a of the connecting-rod 18 guarantees an optimum effectiveness in the blocking of the system, making it possible to cover possible vibration or deformations of the system itself.

Claims

A system (100) for closing and opening at least one leaf (1) of an inward swinging door with respect to a frame (12), said leaf having a main side edge (1a), an exit side edge (1b) and respective top edge (6) and bottom edge, in which
- at one end (6a) near the main side edge (1a), one edge (6) of the leaf (1) is guided by a straight guide (3), secured to the frame and essentially horizontal; and

- in one middle section (6b), the same edge (6) is connected by an articulated connection around a vertical articulation shaft (E1) to an arm (2) mounted to rotate around a pivot shaft (E3), secured to the frame and essentially vertical, all acting as a connecting rod-crank mechanism, with the door leaf (1) performing the connecting-rod function and the arm (2) the crank function;
the system also comprising actuation means (7) to cause the movement to the leaf (1), the system being characterized in that said actuation means (7) comprise an actuator (7a) fixed solidly to one of the leaf (1) or the arm (2), and which applies a moment of force (Mm) on the other of said leaf or arm around the aforementioned articulation shaft (E1).
The system (100) according to the previous claim, characterized in that the first end (6a) of the edge (6) of the leaf (1) is connected by an articulated connection around a shaft (E2) pulled along the length of the straight guide (3) during the maneuvers to open and close the leaf (1) between the end door-closed and door-open positions, and in that in the door-open position, the aforementioned pulled shaft (E2) and the vertical articulation shaft (E1) between the leaf (1) and the arm (2) are aligned along an imaginary line (L) that is essentially perpendicular to the straight guide (3).
The system (100) according to the previous claim, characterized in that in the door-closed position, the aforementioned pulled shaft (E2) and the vertical articulation shaft (E1) between the leaf (1) and the arm (2) are both on the vertical projection of the straight guide (3).
The system (100) according to any of the previous claims, characterized in that the straight guide (3) is positioned below the lintel (11) of the housing compartment for the door arranged in the vehicle frame (12), the guide (3) consequently being essentially coplanar to the door leaf (1) when said leaf (1) is in the closed position.
The system (100) according to any of the previous claims, characterized in that, with the actuator (7a) being solidly connected to the leaf (1), the vertical articulation shaft (E1) is a drive shaft actuated by the actuator (7a) and connected to rotate with the arm (2).
The system (100) according to the previous claim, characterized in that the actuator (7a) comprises a drive shaft (8) and a transmission (9a, 9b) with the articulation shaft (E1) between the leaf (1) and the arm (2), such that the axial rotation of the articulation shaft (E1) in one direction or the other, imparted by the drive shaft (8), modifies the angle formed between the arm (2) and the leaf (1), whose mechanical connections with the pivot shaft (E3) and with the guide (3), respectively, both fixed to the frame (12), impart a compound movement to the leaf (1) towards its open or closed positions.
The system (100) according to the previous claim, characterized in that, with the drive shaft (8) of the actuator (7a) being oriented horizontally, the transmission (9a) comprises a pair of interconnected gears (15,16) with perpendicular shafts, arranged such that a first horizontal-shaft gear (15) is solidly connected to rotate with the drive shaft (8), while a second vertical-shaft gear (16) is solidly connected to rotate with the vertical articulation shaft (E1).
The system (100) according to claim 6, characterized in that, with the drive shaft (8) of the actuator (7a) being oriented horizontally, the transmission (9b) comprises
- a first pair of interconnected gears with perpendicular shafts, arranged such that a first horizontal-shaft gear (15) is solidly connected to rotate with the drive shaft (8), while a second vertical-shaft gear (16) is solidly connected to rotate with a first end (17a) of a thrust arm (17) that is positioned at a level above said second gear (16); said thrust arm (17) in turn being connected by an articulated connection at its other end to a first end (18a) of a transmission connecting-rod (18), and said transmission connecting-rod (18) being connected by an articulated connection at its other end (18b) to an eccentric point of a rotating plate (19); and

- a second pair of vertical-shaft gears, with a third (20) and fourth (21) gears interconnected, arranged such that the third gear (20) is solidly connected coaxially to said rotating plate (19), while the fourth gear (21) is solidly connected to rotate with the vertical articulation shaft (E1) of the arm (2).
The system (100) according to the previous claim, characterized in that when the leaf (1) adopts a position of the door open or partially open, the rotating shaft of the first end (17a) of the thrust arm (17) stays on a same first side of the imaginary line (T) that connects the axes of both connecting-rod (18) ends (18a, 18b), while when the leaf (1) adopts a position of the door closed, the rotating shaft of the first end (17a) of the thrust arm (17) moves to the other side of the aforementioned imaginary line (T) that connects the axes of both connecting-rod (18) ends (18a, 18b), producing an auto-interlocking effect of the transmission (9b) if an attempt is made to move the leaf (1) in the door-open direction.
The system (100) according to any of the previous claims, characterized in that the guide (3) is made up of a profile with an open cross-section that forms a slot, and in that the shaft (E2) pulled along the length of the guide (3) is equipped with a wheel (4) that fits inside said slot.
An installation for closing and opening the two leaves (1) of a double inward swinging door, specifically for doors of passenger transportation vehicles, characterized in that it comprises two systems according to any of the previous claims, symmetrically arranged, and one for each leaf (1), which share a same guide (3).