The present invention relates to a device for locking and closing/opening sliding panels of landing doors of an elevator installation as defined in the preamble of claim 1.

In elevator installations doors with sliding panels are widely used, particularly for landing doors, i.e. those doors that are integral with the masonry structure of a building at the elevator shaft openings, and during normal operation can be only opened when the elevator cabin is level therewith.

It shall be noted in this respect that, in order to prevent accidents caused by wrong opening of landing doors, these doors must be equipped with a safety device that controls locking and closing/opening operations on such landing doors and, during normal operation of the elevator, only allows such landing doors to be opened when they are reached by elevator cabin. Namely, in landing doors with sliding panels an opening device carried by the cabin of the elevator installation will act upon the device for locking and closing/opening the panels of the landing doors to unlock such device and instruct opening or later reclosing of the sliding panels of the landing doors.

In elevator installations the need is strongly felt to further reduce installation space requirements because, especially in existing buildings, the elevator shaft is often small, whereby an excessive bulk of the elevator installation equipment, including the devices for locking and closing/opening the landing doors, would only allow installation of small, low-capacity cabins.

This need is particularly felt in the case of landing doors with sliding panels which are by far the best option for the users of the elevator installation, but require a larger installation space .

Such greater installation space requirements of landing doors with sliding panels are also caused by the presence of the required device for locking and closing/opening the sliding panels of the landing doors. It shall be noted in this respect that prior art installed devices for locking and closing/opening sliding panels of landing doors have a large bulk not only in terms of width and depth, i.e. in the longitudinal direction in which the sliding panels open apart and in the direction perpendicular to the plane of the sliding panels respectively, but also in terms of height, i.e. in the vertical direction in which the elevator cabin extends and moves.

The invention is based on the problem of conceiving and providing a device for locking and closing/opening landing doors with sliding panels of an elevator installation that has such structural and functional characteristics as to fulfill the above need, while obviating the drawbacks as mentioned above concerning the device for locking and closing/opening landing doors with sliding panels of prior art elevator installations.

This problem is solved by a device for locking and closing/opening the landing doors of an elevator installation as defined by the characteristics of claim 1.

Further features and advantages of the device for locking and closing/opening landing doors of an elevator installation of the invention, will be apparent upon reading the following description of one preferred embodiment thereof, which is given by way of illustration and without limitation with reference to the accompanying figures, in which:

- Figure la shows a simplified, schematic front perspective view of a device for locking and closing/opening landing doors of an elevator installation of the invention in an open state after a manual opening operation;

- Figure lb shows a rear perspective view of the device of Figure 1, the guide rail being omitted;

- Figure 2 shows a simplified, schematic front perspective view of the device of the invention in a closed locked state;

- Figure 3 shows a simplified, schematic, partially exploded perspective view of the device of Figure 2;

- Figure 4a shows a simplified, schematic rear perspective view of the device of Figure 2 in an open state;

- Figure 4b shows a simplified, schematic rear perspective view of the device of Figure 4a in one step of the closing movement;

- Figure 4c shows a simplified, schematic rear perspective view of the device of Figure 2 in a closed locked state;

- Figure 4d shows a rear perspective view of the device of Figure la in an open state after a manual opening operation;

- Figure 4e shows a rear perspective view of the device of Figure la during an intermediate step of the manual closing operation;

- Figure 5 shows a simplified, schematic front plane view of the device of Figure 2 in a closed locked state;

- Figure 6a shows a simplified, schematic front plane view of the device of Figure 5 in a closed state, with the lock means in an unlocked state;

- Figure 6b shows a rear plane view of the device of Figure 6a in a closed state, with the lock means in an unlocked state;

- Figure 7 shows a perspective view of the front of a removable double-bridge safety electric contact of the device of the invention;

- Figure 8 shows a rear perspective view of the removable double-bridge safety electric contact of Figure 7;

- Figure 9 shows a simplified exploded perspective view of the removable double-bridge safety electric contact of Figure 7;

- Figure 10 shows a schematic front plane view of the removable double-bridge safety electric contact of Figure 7, with the cover omitted and prior to insertion of the respective removable contact bridges and

- Figure 11 shows a schematic front plane view of the removable double-bridge safety electric contact of Figure 7, with the cover omitted and after insertion of the respective removable contact bridges .

Referring to the accompanying figures, numeral 1 generally designates a device for locking and closing/opening landing doors of an elevator installation according to the invention.

As is known in the art, the elevator installation comprises a masonry structure that defines a hoistway in which an elevator cabin, not shown, moves in a vertical direction V-V. At the various floors, the masonry structure has openings, at which the elevator cabin stops for people or things to come in and out. Each of these openings of the masonry structure has landing doors with sliding panels .

As mentioned at the beginning of the present description, during normal operation of the elevator installation, the landing doors with sliding panels can be only opened when the elevator cabin is thereat. For this purpose, the elevator installation must be equipped with a safety device that controls locking and closing/opening operations on the sliding panels of the landing doors.

According to the embodiment of the figures, the device 1 for locking and closing/opening the sliding panels of the landing doors consists of a device that can control locking and closing/opening operations on two sliding panels, which open apart by moving along the same axis in two opposite directions.

It shall be understood in this respect that in its most general aspect, the invention may also relate to a locking and closing/opening device that controls the operation of:

- a single sliding panel, possibly composed of two or more portions which simultaneously move in the same direction, or

- two sliding panels which simultaneously move in opposite directions, each panel being possibly composed of two or more portions moving in the same direction.

The device 1 of the invention comprises:

- a guide rail 2 which is designed to be secured in a horizontal position to the masonry structure of a building or a framework, at an opening thereof, and extends in a longitudinal direction X-X coinciding with the horizontal direction in which the sliding panels of the landing doors open;

- a first support carriage 3 for supporting a first sliding panel, said first carriage 3 being supported by sliding engagement on said guide rail 2 by rolling means to slide along said guide rail 2 from a retracted limit-stop operating position (see Figures la and 4a) to a forward limit-stop operating position (see Figures 2, 4c and 5), at which the first sliding panel of the landing door that will be supported by said first carriage will be in an open state and a closed state respectively, relative to the opening of the masonry structure;

- stop means 6 against which the first carriage 3 stops to define said forward limit-stop operating position along the guide rail 2, such stop means 6 preventing the first carriage 3 from overreaching said forward limit-stop operating position when moving from the retracted limit-stop operating position to said forward limit-stop operating position;

- lock means for locking the first carriage 3 in said forward limit-stop operating position;

- a first safety electric contact 9 comprising a receiving body which is designed to be fastened to a fixed part of said device 1 for locking and closing/opening sliding panels of landing doors, said receiving body housing therein first contact elements 11 in a protected position, which contact elements can be actuated from outside said receiving body through an actuating key and

- a first actuating key 12 outside said first safety electric contact 9 and suitable to be engaged with the receiving body of said first safety electric contact 9 to cause actuation thereof and establish electrical continuity between said first contact elements 11.

Preferably, said first actuation key is a first removable contact bridge 12 comprising rod-like contacts which are adapted to be inserted, along a first preset insertion/removal path K-K, into first through openings 10 formed in the receiving body of the first safety electric contact 9 to establish electrical continuity between said first contact elements 11.

Alternatively, the first actuation key may be inserted into the receiving body of the safety electric contact to close said electric contact, without forming an electrical continuity bridge between said first contact elements. Preferably, said through openings 10 are formed in a portion of the lower side of the safety electric contact 9 (with the lower side of the electric contact 9 being defined relative to the vertical direction V-V) , such that the rod-like contacts of the first removable contact bridge 12 of the receiving body of the safety electric contact 9 are inserted from the bottom, to prevent any infiltration of dirt or else through the through openings 10.

Preferably, the first carriage 3 will interfere with a portion thereof against the stop means 6 with the interposition of a resilient pad 29, e.g. made of rubber or any other equivalent material.

According to the embodiment of the figures, said rolling means of the first carriage 3 comprise upper rolling means 4 and lower rolling means 5, which are spaced from each other in a vertical direction V-V perpendicular to said guide rail 2. Namely, the first carriage 3 comprises two upper rolling means 4 (which are spaced from each other in the longitudinal direction X-X for stable support of the first carriage 3 by the guide rail 2) and two opposed lower rolling means 5 (which are spaced from each other in the longitudinal direction X-X for stable support of the first carriage 3 by the guide rail 2) . The upper rolling means 4 and the lower rolling means 5 are engaged with an upper rolling track 2a of said guide rail and with a lower rolling track of said guide rail 2 respectively, the upper rolling track and the lower rolling track being defined relative to said vertical direction V-V. Concerning the above mentioned lock means, it will be noted that they can be reversibly actuated to an unlocked state (as shown for instance in Figures 4b, 6a and 6b) from a locked state (as shown in Figures 2, 4c and 5) , defined by a limit-stop abutment, and in such locked state, in a rest condition, the lock means are moved by their weight force. In the above mentioned locked state, said lock means allow the first carriage 3 to be locked in its forward limit-stop operating position, and prevent it from moving away from such position .

Considering the structure of these lock means in greater detail, they comprise:

- a part that defines an abutment 13 supported by one of the first carriage 3 and the guide rail 2 and

- a part that defines a movable engagement member 14 supported by the other of said first carriage 3 and said guide rail 2. It shall be noted that, when the first carriage 3 is in said forward limit-stop operating position and said lock means are in said locked state (see for instance Figures 2, 4c and 5), the movable engagement member 14 and said abutment 13 are mutually engaged (see Figure 4c), thereby preventing any movement of the first carriage 3 from said forward limit-stop operating position to its retracted limit-stop operating position.

Advantageously, when moving from said locked state to said unlocked state and vice versa, the movable engagement member 14 of the lock means is supported in said device 1 to follow a trajectory having a rotation component with respect to a center of rotation defined by a pivot pin 15.

Preferably, the movable engagement member 14 of the lock means is pivotally supported about said pivot pin 15 which extends with a horizontal axis of rotation Y-Y, perpendicular to the guide rail 2.

Advantageously, when the first carriage 3 is in said forward limit-stop operating position (see Figures 2, 4c and 5) the pivot pin 15 of the movable engagement member 14 is interposed between said first safety electric contact 9 and said abutment 13 relative to a direction parallel to the longitudinal direction X-X of the guide rail 2.

Preferably, considering said vertical direction V-V, the axis of rotation of the pivot pin 15 is at such a height that such axis of rotation falls between said upper rolling track 2a and said lower rolling track 2b of said guide rail 2.

As shown in the preferred embodiment of the figures, said abutment 13 is supported by the guide rail 2, and is preferably directly fixed thereto, whereas the movable engagement member 14 is supported by the first carriage 3 and is mounted and hinged thereto by means of said pivot pin 15.

According to one embodiment, the abutment and the stop means may be defined by a single element that is fixed to the guide rail 2, such element acting both as a limit-stop and as an abutment for the lock means.

Therefore, while reference will be made hereinbelow to this particular embodiment, it shall be understood that, in a dual embodiment, not shown, the above mentioned abutment might be mounted aboard the first carriage, whereas the movable engagement member may be pivotally supported by the guide rail.

The first carriage 3 of the device 1 of the invention comprises lateral retention means, which are adapted to engage the guide rail 2 to prevent any lateral displacement of said first carriage from the rail 1 in a horizontal direction perpendicular to the rail, after to an impact or the like.

In the illustrated embodiment, the function of the lateral retention means is accomplished by the engagement member 14, which has a C-shape and is thus adapted to straddle the guide rail 2, as shown in Figures 4c and 4d. Alternatively, a dedicated portion of the carriage is conformed to straddle the guide rail 2 or laterally encircle such guide rail.

As shown in the figures, when said lock means are pivoted into said locking state (see Figure 4c), then said movable engagement member 14 has:

- a first portion 14a located at the same height as the abutment 13, with respect to a direction parallel to the longitudinal direction X-X of said guide rail 2 and

- a remaining portion located at a height other than that of the abutment 13, namely at a greater height than the abutment 13, relative to the vertical direction V-V.

Preferably, the abutment 13 is fixed to a portion of said guide rail 2 that falls between said upper rolling track 2a and said lower rolling track 2b.

According to a preferred and advantageous embodiment, said receiving body of the first safety electric contact 9 is fixed to the guide rail 2, and more preferably is directly fixed to said guide rail 2, substantially proximate to the position assumed by said first carriage 3 in said forward limit-stop operating position (see Figures 2, 4c and 5) .

Preferably, the first safety electric contact 9 is fixed to a portion of the guide rail 2 that falls between said upper rolling track 2a and said lower rolling track 2b.

Preferably, said first removable contact bridge 12 is supported by a pivoting lever 16, which is hinged to the first carriage 3 to pivot about a pivot pin, the latter preferably having a horizontal axis of rotation and extending perpendicular to said guide rail 2.

According to the illustrated embodiment, the pivoting lever 16 is pivoted on the same pivot pin 15 about which the movable engagement member 14 pivots and is pivotally integral with said movable engagement member 14.

Thus, the lever 16 and the first removable contact bridge 12 attached thereto can be pivotally actuated to pivot to and from an angular forward limit-stop position (see Figures 2 and 5) in which, at rest, it is carried by its weight force.

When the first carriage 13 is in said forward limit-stop position and said pivoting lever 16 is in said angular forward limit-stop position (see Figures 2 and 5) , the rod-like contacts of the first removable contact bridge 12 are inserted in the first through openings 10 of the first safety electric contact 9, to establish electrical continuity between the first contact elements 11, as shown in Figure 11.

Conversely, when the pivoting lever 16 is pivoted away from the angular forward limit-stop position, as shown in Figure 6a, the rod-like contacts of the first removable contact bridge 12 are removed from the first through openings 10 of the first safety electric contact 9, as shown in Figure 10.

It shall be noted that, as a result of said integral pivoting motion of the movable engagement member 14 and the pivoting lever 16:

- when the movable engagement member 14 is in said locked state (as shown in Figures 2, 4c and 5) , the pivoting lever 16 is also in the angular forward limit-stop position, and - when the movable engagement member 14 is in said unlocked state (as shown, for example, in Figures 4b, 6a and 6b) , the pivoting lever 16 is pivoted away from said angular forward limit-stop position (see Figure 6a) .

Preferably, the first safety electric contact 9, the abutment 13 and the center of rotation of the pivot pin 15 are in substantially aligned relationship .

As mentioned above, the example of the figures relates to a device 1 that can control locking and closing/opening operations on two sliding panels, which open apart by moving along the same axis in two opposite directions. As a result, the device 1 comprises a second support carriage 18 for supporting a second sliding panel of the landing door.

The second carriage 18 is supported by sliding engagement on said guide rail 2 by upper 19 and lower 20 rolling means to slide along said guide rail 2 from a retracted limit-stop operating position (see Figures la and 4a) to a respective forward limit-stop operating position (see Figures 2, 4c and 5), at which the second sliding panel of the landing door that will be supported by said second carriage 18 will be in an open state and a closed state respectively, relative to the opening of the masonry structure .

It shall be noted that:

- the second carriage 18 in said respective forward limit-stop operating position (see Figures 2,

4c and 5) is placed, along said guide rail, substantially proximate to the first safety electric contact 9;

- the second carriage 18 is kinematically linked to the first carriage 3 to move from its retracted limit-stop operating position to its forward limit- stop operating position and vice versa, at the same time as said first carriage 3 moves from the retracted limit-stop operating position to the forward limit-stop operating position, and vice versa;

- the first carriage 3 and the second carriage 18 move simultaneously along the guide rail 2 in two opposite directions from and to their respective forward limit-stop position at which the first carriage 3 and the second carriage 18 are close together;

- said second carriage 18 supports the second actuation key, in this example a second removable contact bridge 21 which comprises rod-like contacts adapted to be inserted, along a preset insertion/removal path X-X, into the receiving body through second through openings of a safety electric contact to establish electrical continuity between second contact elements 23 of the safety electric contact .

Said safety electric contact engaged by the rod ^¬ like contacts of the second removable contact bridge 21 may be defined by a second safety electric contact, which is independent of said first safety electric contact 9.

Nevertheless, according to the illustrated preferred embodiment (see Figures 7 to 11), the device 1 comprises a single safety electric contact consisting of the first safety electric contact 9, whose receiving body:

- also accommodates therein said second contact elements 23 and

- has second through openings 22 for the rod- like contacts of the second removable contact bridge

21 to fit into the receiving body to contact with the second contact elements 11.

It shall be further noted that:

- the first safety electric contact 9 comprises two distinct wiring points and - the first contact elements 11 and the second contact elements 23 are in such positions as to break the electrical continuity in two corresponding sections of an electric circuit formed within the receiving body of the safety electric contact 9 by electric conductors 26 disposed in series between said two distinct wiring points.

Preferably, said electric conductors 26 include a plurality of conductive plates.

The first contact elements 11 and the second contact elements 23 are supported at respective free end portions of said conductive plates 26 of said plurality of conductive plates.

These free end portions of the conductive plates 26 equipped with the first contact elements 11 and the second contact elements 23 define respective elastic springs to elastically push the first contact elements 11 and the second contact elements 23 toward a forward position, in which the first contact elements 11 and the second contact elements 23 are located substantially at respective through openings 10 and 22.

Thus, upon insertion of the rod-like contacts of the first removable contact bridge 12 into said openings 10 and of the second removable contact bridge 21 into said openings 22, the first contact elements 11 and the second contact elements 23 may reversibly retract into the receiving body by a preset stroke, e.g. of the order of 3÷7 millimeters, against an elastic return action, from said forward position to a more retracted position in the receiving body.

As shown in the figures, said through openings 22 allowing the rod-like contacts of the second removable contact bridge 21 to fit into the receiving body of the first electric contact 9, are formed in a portion of the first safety electric contact 9 which faces the second carriage 18.

When the second carriage 18 is in said forward limit-stop operating position, the rod-like contacts of the second removable contact bridge 21 are inserted in said second through openings 22 of said first safety electric contact 9, to establish electrical continuity between said second contact elements 23.

The second carriage 18 comprises hook means 24 for connection to a corresponding grip portion 25 supported by the first carriage 3 when the first carriage 3 is in said forward limit-stop operating position and the lock means are in their locked state (see Figures 2 and 5) .

Alternatively, according to an equivalent embodiment, the hook means may be carried by the first carriage and the grip portion by the second carriage.

Preferably, said grip portion 25 is supported by the pivoting lever 16 such that, when the first carriage 3 and the second carriage 18 are in their respective forward limit-stop operating positions:

- while said pivoting lever 16 is in said angular forward limit-stop position, said grip portion 25 is engaged with the hook means 24 to join the second carriage 18 to the first carriage 3 (see Figures 2 and 5) , and

- when the pivoting lever 16 is away from said angular forward limit-stop position, said grip portion 25 is disengaged from the hook means 24.

Preferably, in the receiving body of the first electric contact 9 the first through openings 10 and the second through openings 22 are in such arrangement that said first preset insertion/removal path K-K and said second preset insertion/removal path X-X are different and inclined to each other, preferably at an angle of more than 10°, more preferably of more than 45°, or equal to 90°. The first through openings 10 and the second through openings 22 are formed in different walls of the receiving body of the first electric contact 9, preferably in wall portions that are inclined to each other, preferably at an angle of more than 10°, more preferably of more than 45°, or equal to 90°.

Concerning the possibility of pulling the first carriage 3 along the rail 2 to the retracted limit- stop position and especially of imparting the above mentioned rotation to the movable engagement member 14 and the rotating lever 16, which are pivotally integral with each other, it may noted that, for this purpose, the first carriage 3 has special grip-and- pull means which, as is known, are adapted to be engaged and actuated by specially designed grip members (not shown) carried by the cabin of the elevator installation.

According to a first embodiment, said grip-and- pull means for gripping and pulling the first carriage 3 comprise a pair of rollers 27' and 27", with the first roller 27' being directly fixed to the structure of the first carriage 3, and the second roller 27" being supported by the pivoting lever 16. The roller 27" is in such a position with respect to the pivot pin 15 of the pivoting lever 16 that, as said rollers are gripped by grip means (carried by the elevator cabin and not shown) which act upon the rollers 27' and 27" to drive them close together, the pivoting lever 16 pivots to unlock the lock means.

Alternatively, the rollers 27 ' and 27" are replaced by a second pair of rollers 28' and 28", with the roller 28' being directly fixed to the structure of the first carriage 3, and the roller 28" being supported by the pivoting lever 16. In this case, the roller 28" is in such a position with respect to the pivot pin 15 of the pivoting lever 16 that, as said rollers 28' and 28" are gripped by grip means (carried by the elevator cabin and not shown) which act upon the rollers 28' and 28" to drive them away from each other, the pivoting lever 16 also pivots to unlock the lock means.

It shall be noted that, while the figures show both the pair of rollers 27' and 27" and the pair of rollers 28' and 28", the device will only comprise the pair of rollers 27' and 27" or the pair of rollers 28' and 28", according to the particular characteristics of the grip members that are carried by the elevator cabin.

Grip-and-pull means in the form of roller pairs are widely used in the art. Nevertheless, it shall be understood that the device 1 of the invention is adapted to be driven open or closed by grip members carried by the elevator cabin, which are adapted to act upon grip-and-pull means having a form other than that of the above mentioned roller pairs.

In using the device 1 of the invention, once such device has been fixed in the hoistway of a masonry structure, namely above an opening at which the elevator cabin stops for people or things to come in or out, the device 1 is typically in the state as shown in Figures 2, 4c, 5, in which the sliding panels of the landing doors supported by the first carriage 3 and the second carriage 18 are in such position as to prevent access to the hoistway.

In this state, the first carriage 3 is held in the forward limit-stop position due to the interference occurring between the portion 14a of the movable engagement member 14 with the abutment 13 (see Figure 4c) and, at the same time, the pivoting lever 16 is held in the angular forward position in which the rod-like contacts of the first removable contact bridge 12 are inserted in the receiving body of the first safety electric contact 9, through the apertures 10, to contact the first contact elements 11. At the same time, the hook means 24 of the second carriage 18 hookingly engage said corresponding grip portion 25 integral with the first carriage 3, thereby preventing the second carriage 18 from retracting toward its respective retracted limit-stop position.

When the elevator cabin reaches the floor at which the device 1 is located, the sliding panels of the landing floor shall open due to retraction of both carriages 3 and 18 along the guide rail 2 to their respective retracted limit-stop positions, as shown in Figure 5. This displacement is controlled by the grip members carried by the elevator cabin, which come to engagement with the grip-and-hold means with which the first carriage 3 is equipped (the pair of rollers 27' and 27" or the pair of rollers 28' and 28") to move the first carriage 3 along the guide rail 2.

It should be reminded in this respect that the first carriage 3 and the second carriage 18 are kinematically linked, whereby by controlling retraction of the first carriage 3, the second carriage 18 will also retract. Alternatively, both carriages 3 and 18 may be acted upon to cause displacement along the guide rail 2.

In order to cause retraction of the first carriage 3, the lock means must be first moved from the initial locked state (see Figures 2, 4c and 5) to the unlocked state (see Figure 6b), in which the portion 14a of the movable element 14 overreaches the height of the abutment 13, without preventing the first carriage 3 from retracting toward the retracted limit-stop position.

As described above, the lock means are unlocked by the action of the grip means carried by the elevator cabin which engage the grip-and-hold means with which the first carriage 3 is equipped, and move the pair of rollers 27' and 27" toward each other or the pair of rollers 28' and 28" away from each other, thereby causing the movable engagement member 14 to pivot (in the counterclockwise direction of arrow F of Figure 6b) relative to the pivot pin 15 that ensures support thereof by the first carriage 3.

It should be noted that such rotation of the movable engagement member 14 causes a corresponding rotation of the pivoting lever 16 about the pivot pin 15 (see Figure 6a) , as a result of which:

- the rod-like contacts of the first contact bridge 12 will be disengaged from the receiving body of the first contact 9 (see Figure 10) and

- said grip portion 25 is carried by the pivoting lever 16 to disengagement from the hook means 24 of the second carriage 18.

As a result, both the first carriage 3 and the second carriage 18 are free to be pulled to their respective limit-stop positions by the grip members that are carried by the elevator cabin.

As the sliding panels of the landing doors are closed, from the state as shown in Figure 4a, in which the grip members carried by the elevator cabin hold the movable engagement member 14 rotated in the unlocked state against the action of the weight force, the two carriages 3 and 18 are free to be pulled along the guide rail 2 to its forward limit- stop position.

Once said forward limit-stop operating position has been reached by the first carriage 3, the first portion 14a has fully overreached the abutment 13 along the guide rail 2 and, when the grip members carried by the elevator cabin no longer exert their action on the grip-and-pull members of the device 1 (the pair of rollers 27' and 27" or the pair of rollers 28' and 28"), the weight force exerted on the movable engagement member 14 will cause the whole movable engagement member 14 to rotate in the direction opposite to the previous direction, into said locked operating state (see Fig. 4c) .

It should be noted that said counter-rotation of the movable engagement member 14 causes:

- insertion of the rod-like contacts of the first removable contact bridge 12 into the receiving body of the first safety electric contact 9 through the openings 10, such insertion following a circular path which, at the openings 10, becomes an insertion removal path K-K substantially coinciding, in its end portion, to said vertical direction V-V, and

- coupling of the grip portion 25 supported by the first carriage 3 to the hook means 24 of the second carriage 18.

The second contact bridge 21 may be advantageously integrally supported by the second bridge 18, at the side facing the first carriage 3 and such that the rod-like contacts extend in the longitudinal direction X-X and face toward the safety electric contact 9, in whose body they fit in said insertion direction X-X.

The device 1 of the invention is also designed to allow the sliding panels of the landing doors to be manually opened and closed by an operator that performs maintenance on the elevator installation.

These manual opening and closing operations on the sliding panels will be now described.

The lock means are locked by rotation of the movable engagement member 14 from the locked state (as shown in Figures 2, 4c and 5) to the unlocked state (e.g. as shown in Figures 4b, 6a and 6b) , by manually inserting and rotating an unlocking key in a keyhole (not shown) .

Once the lock means have been unlocked, the operator may manually push the panel supported by the first carriage 3, from the forward limit-stop operating position toward the retracted limit-stop operating position as shown in Figure la, and simultaneously retract the second carriage 18 toward its retracted limit-stop position due to the above mentioned kinematic linkage between the first carriage 3 and the second carriage 18.

It shall be noted that, as soon as the operator stops acting upon the unlocking key in said keyhole, the weight force acts on the movable engagement member 14 and moves it back to the locked state.

When the sliding panel supported by the first carriage 3 is manually closed at a later time, the first carriage 3 moves along the guide rail 2 from the retracted limit-stop operating position toward the forward limit-stop operating position. During such movement, an interference fit occurs between interfering surfaces of the movable engagement member 14 that is pivotally supported by the first carriage 3 and the abutment member 13 that is fixed to the guide rail 2, at least one of said interfering surfaces (in this example the lower surface 14b of the movable engagement member 4) being inclined with respect to the longitudinal direction X-X of said guide rail 2 to define a chute that causes a relative displacement in the vertical direction V-V between the movable engagement member 14 and the abutment 13 (in the example of Figure 4e to raise the whole movable engagement member 14 above the abutment 13), thereby allowing said first portion 14a of the movable engagement member 14 to overreach the abutment 13 along said guide rail 2. In other words, as the first carriage 3 moves toward the forward limit-stop position, the lower surface 14b of the movable engagement member 14 comes to interference with the abutment 13 which, as shown in Figure 4b, it causes the whole movable engagement member 14 to rotate (in the direction of arrow C) about the pivot pin 15, with the portion 14a of the movable engagement member 14 being raised above the abutment 13. As a result of this rotation of the engagement member 14, the portion 14a of the movable engagement member 14 overreaches the abutment 13 along the guide rail 2, without interfering therewith.

As the first carriage 3 reaches said forward limit-stop operating position, said first portion 14a of the movable engagement member 14 comes again, due to its weight force, at the same height as the abutment 13, with respect to a direction parallel to the longitudinal direction X-X of said guide rail 2. In this state (see Figure 4c), said first portion 14a of the movable engagement member 14 abuts against the abutment 13 to counteract the back movement of said first carriage 3 toward said retracted limit-stop operating position.

It shall be noted that, due to said kinematic linkage between the first carriage 3 and the second carriage 18, as the panel supported by the first carriage 3 is manually opened or closed it causes the panel supported by the second carriage 18 to also open or close, respectively.

As clearly shown in the above description, the device for locking and closing/opening sliding panels of landing doors of an elevator installation according to the present invention fulfills the above mentioned need and also obviates prior art drawbacks as set out in the introduction of this disclosure. Indeed, the particular structure of the device 1 can limit the bulk of the device and also facilitates and simplifies he installation of the various parts of the device, thereby improving effectiveness and reliability of the operation of the device of the invention, while limiting the overall costs of the structure as compared with similar prior art devices. Particularly, the device of the invention eliminates the need of providing brackets, that are usually found in prior art devices for supporting contacts, stop members, engagement members and the like, and further avoids the need of installing separate parts, that also require adjustment after installation.

It should be noted that most of prior art devices for locking and closing/opening sliding panels of landing doors of an elevator installation require a load-bearing structure and adjustment after assembly, because the safety electric contact is generally mounted to a structure other than the guide rail and the limit-stop member of the sliding panel is separate from the parts of prior art devices.

The device for locking and closing/opening sliding panels of landing doors according to the invention avoids the need for independent load- bearing structures for the various parts, and requires almost no adjustment, as both the limit-stop means for the first carriage and the safety electric contact are mounted to the guide rail. This is possible because the lock/stop member and the safety electric contact are mounted in a position opposite to the pivot pin of the lock means.

The use of a safety electric contact that is configured as a double contact for simultaneous insertion of two distinct contact bridges further simplifies the structure and assembly of the device, such that further contacts would not require particular wiring arrangements or position adjustments relative to the guide rail.

Those skilled in the art will obviously appreciate that a number of changes and variants may be made to the device for locking and closing/opening sliding panels of landing doors of an elevator installation as described hereinbefore, without departure from the scope of the invention, as defined in the following claims.