The present invention relates to a door coupler as de¬ fined in the preamble of claim 1 and to a locking device as defined in the preamble of claim 6.

In elevators provided with automatic doors, the coupling between the car door and the landing door is generally implemented using a door coupler which is mounted on the car door and which, by means of its gripping elements, engages counterparts mounted on the landing door. The door coupler and the counterparts are so fitted relative to each other that, when the elevator car is moving past the landing door, the counterparts on the landing door pass between the gripping elements of the door coupler. When the car is at a landing and the car doors are mov¬ ing, the door coupler is in engagement with the counter¬ parts. In this way, the landing door moves together with the car door when the latter is moved by a power means connected to the car door. Often the gripping elements are metal vanes projecting from the door coupler towards the landing door and forming a kind of a vertical slot which is open towards the landing door. The counterparts used often consist of rollers mounted on the landing door and projecting from the door towards the elevator shaft, the axle of the rollers being mounted in a posi¬ tion perpendicular to the plane of the door. In conjunc¬ tion with the door coupler or the car door itself there is a locking device which closes the car door so that it cannot, at least without special measures, be opened except when the elevator car is near a landing, i.e. when the elevator car is within the so-called door zone. The locking system of an elevator door must be reliable and durable. The locking of an elevator door should not produce any disturbing noise.

There are various arrangements for locking the elevator door in a manner that is reliable and suited for use

with an elevator door. For instance, a locking system operated by a separate electromechanical actuator re¬ quires that the elevator has a separate subsystem or a parallel system for the control of door operation that takes care of locking and unlocking the door. A locking system using a separate electromechanical actuator al¬ ways involves an additional cost corresponding to the prize of the actuator.

There are also mechanical locking systems in which the actuating force for locking the door is taken from the motion of the elevator car or the car door. In such sys¬ tems the landing zone is indicated and/or the operation of the lock is controlled by means of a separate slide or other sign provided in the elevator shaft at each landing and immovably fixed in place with respect to the elevator shaft. Mounting such slides or signs in the elevator shaft at each landing requires plenty of in¬ stallation time. A long installation time means high la- bour costs .

Often the locking arrangement occupies a large space and therefore the placement of the locking devices more or less dictates the design of the door or door suspension of the elevator car.

To meet the need to achieve a simple, mechanically oper¬ ated locking device for the door of an elevator car which is applicable for use in a modern elevator envi- ronment and in modern elevator technology and is cheap to manufacture and advantageous in respect of space utilization, easy to install, noiseless in operation and is integrated with the door coupler, a new type of door coupler and a new type of locking system are presented as an invention. The door coupler of the invention is characterized by what is presented in the characteriza¬ tion part of claim 1, and the locking device of the in¬ vention is characterized by what is presented in the

characterization part of claim 6. Other embodiments of the invention are characterized by what is presented in the other claims.

The advantages achieved by the invention include the following:

- the locking device is cheap to manufacture.

- being integrated with the door coupler, the locking device permits the application of a simpler door con- cept. Integrating the door coupler with the locking sys¬ tem simplifies the installation.

- since the locking is controlled by the operation of the door coupler, in other words, by the presence or ab¬ sence of a counterpart attached to a landing door within the reach of a gripping element of the door coupler, the elevator shaft need not be provided with separate con¬ trol devices or signs to indicate door zones.

- the locking device is of a construction that does not take up much space, so it is not difficult to acco mo- date it even in thin structures.

- the locking device is easy to install in conjunction with the door and, being mechanically controlled, re¬ quires no electric actuating equipment.

- the door remains locked when outside landing zones, the locking is not affected by possible disturbances in the electrical system of the elevator.

- if in the event of a power failure the elevator has stopped between floors, the door can be opened after the elevator has been moved manually to a landing. - the equipment does not produce any extra noise when the elevator is running or when the car door is being locked or unlocked.

- the locking and unlocking of the car door of the ele¬ vator is dependent on the opening and closing of the door both mechanically and in respect of time.

In the following, the invention is described in detail by the aid of an example embodiment by referring to the attached drawings, in which

Fig. 1 and 2 present a door coupler applying the in¬ vention together with a locking system when the car is outside the landing zone, and Fig. 3 and 4 present a door coupler applying the in- vention together with a locking system when the car is within the landing zone.

In the description, parts are designated by using terms such as left, right, upper, lower, etc. These terms re- fer to the corresponding directions in the figures, and so do the expressions "clockwise" and "anticlockwise".

A door coupler 4 with a lock applying the invention and its operation are described by referring to figures 1-4. Fig. 1 and 2 present a situation where the elevator car is outside the landing zone and the door coupler vanes 14 and 15 cannot meet the rollers constituting the coun¬ terparts on the landing doors. Fig. 3 and 4 present a situation where the elevator car is within the landing zone and the vanes 14,15 engage the rollers 17,18 on the landing door when the doors are opened. The door coupler 4 is mounted on the car door suspension plate 1. The car door suspension plate 1 is provided with supporting rollers and usually also counter rollers, which run along a guide rail or other suitable guide surface on the overhead supporting beam fixed to the elevator car. Thus, supported by the suspension plate(s), the door is suspended from the overhead supporting beam.

The door coupler vanes 14 and 15, between which the rollers 17 and 18 (shown in Fig. 4) attached to the landing door will go when the door coupler engages the landing door, are attached to a linkage system 2 actu-

RECT1REDSHEET(RULE91)

ated by the car door drive. Connected to the linkage 2 is also a lock catch 10 that locks the car door. The lock catch engages a detent immovable relative to the car door, mounted e.g. on the overhead beam supporting the door, or possibly a door panel moving in the oppo¬ site direction. The car door actuator opens and closes the car door. It also opens and closes the landing door, which is coupled to the car door via the door coupler. The car door actuator is e.g. a rope drive acting in the directions of the opening and closing movements of the door and attached to the door coupler 4. Instead of a rope drive, the door actuator may be some other type of drive means, such as a hydraulic cylinder, that produces a driving force acting in the direction of the car door movement. The doors are actually moved by means of the door coupler. The rope drive is connected to the linkage 2 via connection point 3 on the operating lever 5. Due to the action of the rope drive, the operating lever 5 tends to turn, within the limits of its range of motion, in the direction of the rope pull about its pivot 6, which is immovable in relation to the door coupler 4 (and to the suspension plate 1 supporting the door cou¬ pler) . The operating lever 5 is connected to the suspen¬ sion plate 1 via pivot 6, permitting a turning movement. The motion of the operating lever 5 about its pivot 6 produces via the linkage 2 an appropriate movement of both the lock catch 10 and the vanes 14 and 15. The movement appropriate in each case depends on whether the elevator is within a door zone or not. The information as to whether the elevator is within a door zone is ob¬ tained on the basis of the presence of landing door rollers in the gap between the vanes 14 and 15. There¬ fore, the height of the gap between the vanes 14 and 15 must be substantially equal to the height of the door zone.

Fig. 1 shows arrows close and open starting from the connection point 3. The close arrow indicates the direc-

tion (to the left in the figure) in which the rope drive pulls the door when it is being closed, while the open arrow indicates the direction (to the right in the fig¬ ure) in which the rope drive pulls the door when it is being opened. The close arrow also indicates the direc¬ tion of the closing movement of the door and the open arrow the direction of its opening movement. In Fig. 1, the angle through which the operating lever 5 turns an¬ ticlockwise about pivot 6 when the rope drive is trying to open the door is indicated by a sector 6a depicted at pivot 6. The turning movement of some other parts 7,8,9 in the linkage caused by the turning of the operating lever 5 is indicated by sectors 7a, 8a, 9a shown on the appropriate parts. These parts 7,8,9 of the linkage turn about pivots 7b, 8b, 9b immovable with respect to the door coupler. These pivots 7b, 8b, 9b that are immovable in re¬ lation to the door coupler are indicated in the figures with a filled (blackened) circle. All other pivots and connection points that are immovable with respect to the door coupler are also indicated by filled circles . Piv¬ ots and connection points moving with the parts of the linkage are indicated with an empty (white) circle. Fig. 2 shows the positions of the parts of the linkage, the door coupler vanes 14 and 15 and the lock catch 10 in which they have ended up as a result of the action of the linkage 2 caused by the motion of the operating lever.

In the following is a description of how the kinetic ef- feet resulting from the operating lever 5 turning through sector 6a is transmitted in the linkage 2. The operating lever 5 is connected to the linkage via three movable pivots 5x, 5y and 5z. Below the operating lever 5 there is a supporting lever 21 which is turnably con- neeted to an immovable pivot 21a and which has movable pivots 21x and 21y on it. The lever arms between pivots 21a and 21x and between pivots 6 and 5x, respectively, are of equal length. Similarly, the lever arms between

pivots 21a and 21y and between pivots 6 and 5y, respec ^¬ tively, are of equal length. The left vane 14 is con¬ nected to the operating lever 5 and to the supporting lever 21 via pivots 5x and 21x. Connected to the operat- ing lever 5 and the supporting lever 21 is a synchroniz¬ ing bar 16 via pivots 5y and 21 y in such manner that pivots 5x, 21x, 5y and 21y constitute the corner points of a rhomboid, so that the left vane 14 and the synchro¬ nizing bar 16 are parallel to each other, the lever arms between pivots 21a and 21x and between 6 and 5x are par¬ allel to each other and the lever arms between pivots 21a and 21y and between 6 and 5y are parallel to each other. In fact, as far its movements are concerned, the synchronizing bar 16 corresponds to the vane of an ordi- nary door coupler corresponding to vane 15, and this vane 15, which acts as a slide vane actuating the lock, is a detached surface structure of the synchronizing bar 16 which, when departing from the immediate vicinity of the synchronizing bar 16, prevents the lock catch 10 from being released. Connected to the operating lever 5 at pivot 5z is the left end of a first rod 22, which connects the operating lever 5 to an upper triangular lever 7. The rod has between its ends a joint 22a that permits bending of the rod. The upper triangular lever 7 is held by an immovable pivot 7b. Around this pivot 7b, the upper triangular lever has pivots 7x,7z and a con¬ nection point for a draw-spring 23 which move with the triangular lever. Connected to the uppermost pivot 7z is the right-hand end of the rod 22. When the rod 22 moves right as the operating lever 5 is turning in the clock¬ wise direction, the triangular lever 7 also turns clock¬ wise. This clockwise turning motion is assisted by the draw-spring 23, which applies a pull at the connection point 7y on the right, acting in a downward direction towards the point 23a of connection of the draw-spring on the suspension plate. No draw-spring 23 would be needed if the rod had no joint 22a. The clockwise rota¬ tion of the first triangular lever 7 causes the left-

hand pivot 7x on the triangular lever 7 to move upwards, thus drawing the right-hand movable pivot 8y of a second triangular lever 8 upwards by means of a second rod 24, causing triangular lever 8 to turn anticlockwise about pivot 8b, with the result that the left-hand pivot 8x moves right. The first end of the second rod 24 is con¬ nected to pivot 7x and the second end to pivot 8y. The pivots 8b,8b,8y of triangular lever 8 are located near the corners of the triangular lever 8.

In fact, the above description of the movements of the various parts of the linkage applies both inside and outside the landing zone and the movements take place in consequence of the operating lever 5 turning through an angle corresponding to sector 6a when the door control reference, in other words the pull produced by the door drive, changes from the close direction to the open di¬ rection.

Now, referring to Fig. 1 and 2, a situation will be de¬ scribed where the elevator car is outside the landing zone, and then, referring to Fig. 3 and 4, a situation where the elevator car is within the landing zone.

Connected by its first end to pivot 8x on triangular lever 8 is a third rod 25. Via a pivot 25a between its ends, the third rod 25 is turnably attached to the right-hand end of a substantially L-shaped locking lever 11. The locking lever 11 remains substantially station- ary, and this is ensured by a compression spring 12 which applies an upward pressure to the left-hand end of the locking lever, which in turn presses the lock catch 10 towards the locked position. The drawings show the springs 12 and 23 only in Fig. 1. As the triangular lever 8 causes the first end of the rod 25 connected to pivot 8x to move right, the rod 25 turns about pivot 25a, with the result that the second end of the rod moves left and, via a fourth rod 26, applies a force to

pivot 27a between the ends of the first suspension lever 27 of vane 15, causing said lever 27 to turn left. The first end of the fourth rod 26 is connected via pivot 25x to the second end of the third rod 25, while the second end of the fourth rod 26 is connected to pivot 27a on the first suspension lever 27. Vane 15 is con¬ nected to the door coupler via two suspension levers 27 and 28. The first suspension lever 27 and the second suspension lever 28 are tumably connected to the sus- pension plate 1 supporting the door coupler via the piv¬ ots 27x and 28x at their first ends, which are immovable in relation to the door coupler. The second ends of the suspension levers 27 and 28 are connected to vane 15 via pivots 27y,28y. The two suspension levers 27 and 28 are of the same length. Pivots 27y, 28y, 27x and 28x are so disposed relative to each other and to the suspension plate 1 that, when the suspension levers 27,28 are turn¬ ing, vane 15 remains aligned in a vertical direction. Thus, the motion of the linkage will not release the lock when the car is outside the landing zone, but merely causes vane 15 to move to the left. The compres¬ sion spring 12 ensures that the vane will move to the left. Due to the force applied by the compression spring to the locking lever 11, pivot 25a remains stationary while pivot 25x is moving.

Referring to Fig. 3 and 4, a situation is now described where the elevator car is in a landing zone and the locking of the car door is released.

Fig. 3 shows a sector 6a at pivot 6 to indicate the an¬ gle through which the operating lever 5 first turns in the anticlockwise direction to release the lock, and an¬ other sector 6A through which the operating lever 5 sub- sequently turns to permit the door coupler 4 to engage the rollers 17,18 on the landing door.

In the manner described above, the action of the linkage produces, among other things, turning movements of the triangular levers 7 and 8, as indicated by the sectors 7a and 8a depicted on top of said levers. Since the right-hand vane 15, when the elevator car is within the landing zone, is pressed against the right-hand roller 18, some of the various parts of the linkage move in a different way than when the car is outside the landing zone. As stated above. Roller 18 is, so to speak, a fixed roller, in other words, it is the one of the roll¬ ers that remains substantially immovable in the horizon¬ tal direction relative to the landing door when the door coupler vane is pressed against it. On the other hand, roller 17 can move through some distance relative to the landing door, so the movement produced by the pressure applied to this roller by door coupler vane 14 can be used to release the lock of the landing door. As vane 15 is pressed against roller 18, this prevents it from mov¬ ing to the left. An important movement in respect of the desired operation is the clockwise turning movement of the third rod 25 about pivot 25x through an angle indi¬ cated by sector 25A that takes place as a result of the anticlockwise rotation of triangular lever 8.

Fig. 4 shows the positions of the parts of the linkage 2, the door coupler vanes 14 and 15 and the lock catch 10 in which they have ended up as a result of the action of the linkage caused by the operating lever moving through an angle corresponding to sector 6a. Connected to pivot 8x on triangular lever 8 is the first end of rod 25, whose lower end is connected to the fourth rod, and the pivot 25x at its end acts as the fulcrum of its turning movement when its upper end is moved to the right by the triangular lever. Since the movement of the right-hand vane 15 and therefore also the movement of suspension lever 27 is prevented, the pivot 25x at the right-hand end of the fourth rod acts as a substantially immovable fulcrum for the turning movement of the third

rod 25. In this situation, the effect of the compression spring 12 on lever 11 is outbalanced by the supporting force indirectly received by pivot 25x. Consequently, the pivot between the ends of the third rod to which the L-shaped locking lever 11 is connected is drawn through a certain distance to the right. The pull resulting from the movement of the locking lever 11 releases the lock catch 10, thus permitting the opening movement of the car door to be started. At the same time, a safety switch 13 provided in conjunction with the lock catch 10 is opened. From the safety switch, an electric signal indicating whether the car door is locked or not is sup¬ plied to the safety circuit and, if necessary, to the control system of the elevator. After the lock has been released, the operating lever will turn further through a distance corresponding to sector 6A as shown in Fig. 3. This movement of the operating lever causes the right-hand door coupler vane 14 to move into contact with the right-hand roller 17 on the landing door and finally the door coupler rollers 17,18 to be pressed be¬ tween the door coupler vanes 14,15, resulting in com¬ plete coupling between the landing door and the car door. The operating lever is free to turn through sector 6A because lever 22 is provided with a joint 22a that permits the rod to bend so that its motion towards tri¬ angular lever 7 after the release of the lock is sub¬ stantially completely received by the bending of the rod 22.

It is obvious to a person skilled in the art that dif¬ ferent embodiments of the invention are not limited to the examples described above, but that they can be var¬ ied within the scope of the claims presented below.