FRAME FOR A LANDING DOOR OF AN ELEVATOR

Technical field

The present invention relates to a frame for a landing door of an elevator. The frame applies both to landing doors with a central opening and lateral (telescopic) opening.

Background art

As is known, each landing door comprises a frame consisting of two lateral jambs, a crossbar (sometimes also indicated as the "top jamb") and a lower profile consisting of the combination of the sill that can be walked upon and of the subsill.

The dimension of the elements making up the frame is selected so as to adapt to a well-defined opening of the door. Thus, for each elevator installation it is necessary to have four elements the dimensions of which are sized to match the specific opening required.

In order to meet this need, the manufacturer is forced to manage the production of pieces "made to measure" according to the dimensions required in the specific installation.

The customized management of each order entails long waiting times for the end customer, with resulting high running costs for the manufacturer (restarting manufacturing plants whenever a new order is requested, necessity of on-site inspections to check measurements before production, etc.).

Alternatively, the manufacturer could decide to use a warehouse for pieces that enables some "standard" frames to be manufactured, with "standard" frames being defined here as frames having the dimensions that are most frequently requested. For example, let 9 standard frames be considered, corresponding to three different width sizes combined singly with three different height measurements.

This entails having to store three types of lateral jamb (corresponding to three different frame heights), three types of crossbar (corresponding to three different frame widths) and three types of lower profile (corresponding to three different frame widths).

The number of pieces of different type complicates inventory logistics. In all cases, if during the installation phase measuring errors are encountered it is necessary to suspend work, make the piece of the right size arrive and resume work subsequently.

Management of this type is extremely rigid, complex and costly.

At most, solutions are known that enable possible tolerances to be adjusted during the assembly step, which tolerances are linked to the non- ideal nature of the components. For example, US4489527 refers to a frame-height adjusting system, whereas US5445244 relates to the adjustment of the width of the frame.

Document FR2125322 refers to a frame for a door according to the preamble of claim 1 .

Document FR2820455 shows a sill supported by a fixed support.

Disclosure of the invention

In this context, the technical task underlying the present invention is to propose a frame for a landing door of an elevator which overcomes the drawbacks in the prior art as described above.

In particular, the aim of this invention is to make available a frame for a landing door of an elevator that can be used for different sizes of door opening.

Another aim of the present invention is to make available a frame for a landing door of an elevator the manufacture of which is simplified with respect to known solutions.

Another aim of the present invention is to make available a frame for a landing door of an elevator that simplifies the management of warehouse inventory and shortens delivery times to the end customer.

A further aim of the present invention is to propose a frame for a landing door of an elevator that is easy and fast to assemble.

The technical task and the aims specified are substantially achieved by a frame for a landing door of an elevator defining an opening, comprising:

- two substantially parallel lateral jambs;

- a crossbar;

- a sill;

- first fixing means for fixing the crossbar to upper ends of the lateral jambs;

- second fixing means for fixing the sill to lower ends of the lateral jambs. The upper end of each lateral jamb has a recess shaped so as to support one of the two ends of the crossbar, so that the crossbar and the upper ends of the jambs are mutually slidable to allow the lateral jambs to move towards and away from one another. The first fixing means is configured for fixing each end of the crossbar to the upper end of the corresponding lateral jamb for each position that the crossbar can assume with respect to the lateral jambs.

The second fixing means comprises at least one support bracket supporting the sill at the lower end of each of the lateral jambs.

The lower end of each lateral jamb has a series of through holes aligned along the prevalent extension of the lateral jamb. The second fixing means comprises a screw or rivet which, when joining the corresponding support bracket to the lower end of the lateral jamb, crosses one of the aligned through holes so that the sill is located at a pre-established height with respect to the lateral jambs.

Preferably, the recess is substantially L-shaped.

According to one embodiment, the upper end of each lateral jamb has at least one through slot having an elongated extension that is substantially transversal to the prevalent extension of the corresponding lateral jamb. The first fixing means comprises a further screw or rivet which, when joining the crossbar to the upper end of the corresponding lateral jamb, crosses the through slot in a variable position according to the desired opening.

According to another embodiment, the upper end of each lateral jamb has a further series of through holes aligned transversally with respect to the prevalent extension of the corresponding lateral jamb. The first fixing means comprises a further screw or rivet which, when joining the crossbar to the upper end of the lateral jamb, crosses one of the through holes so that the crossbar assumes a pre-established position with respect to the lateral jambs.

Preferably, the frame comprises a reinforcement plate for each end of the crossbar. The first fixing means is operatively active also on the reinforcement plate to fix the reinforcement plate to the end of the crossbar and to the upper end of the corresponding lateral jamb.

Brief description of drawings

Further characteristics and advantages of the present invention will become more apparent from the following indicative, and hence non- limiting, description of a preferred, but not exclusive, embodiment of a frame for a landing door of an elevator, as illustrated in the appended drawings, in which:

- figure 1 illustrates a frame for a landing door of an elevator, according to the present invention, in a frontal view;

- figures 2 and 3 illustrate two embodiments of the crossbar of the frame of figure 1 , in a perspective view;

- figure 4 illustrates the upper end of a lateral jamb of the frame of figure 1 , in a perspective view;

- figures 5 and 6 illustrate an assembly detail of the frame of figure 1 (upper end of a lateral jamb and end of the crossbar), respectively in an exploded rear view and in an exploded frontal view;

- figures 7a, 7b and 7c illustrate different positions of the crossbar with respect to the lateral jambs for as many dimensions of the opening defined by the frame, in a frontal view;

- figures 8 and 9 illustrate an assembly detail of the frame of figure 1 (lower end of a lateral jamb and sill), in an exploded frontal view and in an exploded rear view, respectively. Detailed description of preferred embodiments of the invention

With reference to the figures, number 1 indicates a frame for a landing door of an elevator, comprising two substantially parallel lateral jambs 2, 3, a crossbar 4 and a sill 5.

The crossbar 4 is fixed to the upper ends 2a, 3a of the lateral jambs 2, 3 by first fixing means 6.

The sill 5 is fixed to the lower ends 2b, 3b of the lateral jambs 2, 3 by second fixing means 7.

The frame 1 surrounds an opening 100 having a pre-established extension.

Originally, the upper end 2a, 3a of each lateral jamb 2, 3 has a recess 8 shaped so as to support one of the two ends 4a, 4b of the crossbar 4. Preferably, the recess 8 is substantially L-shaped, as can be seen in figure 4.

Owing to this recess 8, the crossbar 4 and the upper ends 2a, 3a of the lateral jambs 2, 3 are mutually slidable to allow the lateral jambs 2, 3 to move towards and away from one another, i.e. to allow the dimensions of the opening 100 defined by the frame 1 to be varied.

Advantageously, the first fixing means 6 is configured to fix each end 4a, 4b of the crossbar 4 to the upper end 2a, 3a of the corresponding lateral jamb 2, 3 for each position that the crossbar 4 can assume with respect to the lateral jambs 2, 3 (i.e. for each opening 100 that can be set for the frame 1 ).

For example, figures 7a, 7b and 7c illustrate different positions of the crossbar 4 with respect to the lateral jambs 2, 3 for as many dimensions of the opening 100 defined by the frame 1 .

The crossbar 4 always remains fixed whereas the lateral jambs 2, 3 are moved away from one another when passing from the configuration of figures 7a, 7b and 7c.

The second fixing means 7 comprises at least one support bracket 13 supporting the sill 5 at the lower end 2b, 3b of each of the lateral jambs 2, 3.

The lower end 2b, 3b of each lateral jamb 2, 3 has a series of through holes 14 aligned along the prevalent extension of the lateral jamb 2, 3. The second fixing means 7 comprises at least one screw or rivet 15 which, when joining the corresponding support bracket 13 to the lower end 2b, 3b of the lateral jamb 2, 3, crosses one of the through holes 14 so that the sill 5 is located at a pre-established height with respect to the lateral jambs 2, 3. In this context, the phrase "height of the sill" refers to the assembled frame so that the lateral jambs are vertical with respect to the ground or floor and the sill is located at a certain height from the ground or floor.

In a first embodiment, illustrated in figures 4 to 7, the upper end 2a, 3a of each lateral jamb 2, 3 has at least one through slot 9 having an elongated extension substantially transversal to the prevalent extension of the corresponding lateral jamb 2, 3.

For each lateral jamb 2, 3 the first fixing means 6 comprises a further screw or rivet 10 which, when joining the crossbar 4 to the upper end 2a, 3a of the lateral jamb 2, 3 crosses the through slot 9 in a variable position according to the desired opening 100.

Preferably, in the upper end 2a, 3a of each lateral jamb 2, 3 two parallel through slots 9 are obtained, the through slots having an elongated extension that is substantially transversal to the prevalent extension of the corresponding lateral jamb 2, 3.

In this case, for each lateral jamb 2, 3 the first fixing means 6 comprises two screws or two rivets 10 which, when joining the crossbar 4 to the upper end 2a, 3a of the lateral jamb 2, 3, cross the through slots 9 in variable positions according to the desired opening 100 (see figures 7a, 7b, 7c).

In a second embodiment that is not illustrated, a through slot is obtained in each end 4a, 4b of the crossbar 4 rather than in the upper end 2a, 3a of each lateral jamb 2, 3. In this case, the through slot has an elongated shape along the prevalent extension of the crossbar 4. For each lateral jamb 2, 3 the first fixing means 6 comprises a further screw or rivet 10 which, when joining the crossbar 4 to the upper end 2a, 3a of the lateral jamb 2, 3 crosses the through slot of the crossbar 4 in a variable position according to the desired opening 100.

Also in this second embodiment, in each end 4a, 4b of the crossbar 4 two parallel through slots can be obtained having an elongated shape along the prevalent extension of the crossbar 4.

In a third embodiment that is not illustrated, the upper end 2a, 3a of each lateral jamb 2, 3 has a further series of through holes aligned transversally with respect to the prevalent extension of the corresponding lateral jamb 2, 3.

For each lateral jamb 2, 3 the first fixing means 6 comprises a further screw or rivet 10 which, when joining the crossbar 4 to the upper end 2a, 3a of the lateral jamb 2, 3, crosses one of the through holes of the further series so that the crossbar 4 assumes a pre-established position with respect to the lateral jambs 2, 3 (corresponding to the desired opening 100).

In a fourth embodiment that is not illustrated, the through holes are obtained in each end 4a, 4b of the crossbar 4 rather than in the upper end 2a, 3a of each lateral jamb 2, 3. In this case, the through holes are aligned according to the prevalent extension of the crossbar 4.

For each lateral jamb 2, 3 the first fixing means 6 comprises a further screw or rivet 10 which, when joining the crossbar 4 to the upper end 2a, 3a of the lateral jamb 2, 3, crosses one of the through holes so that the crossbar 4 assumes a pre-established position with respect to the lateral jambs 2, 3 (corresponding to the desired opening 100).

In one embodiment, illustrated in figure 3, the frame 1 comprises a reinforcement plate 12 for each end 4a, 4b of the crossbar 4.

This reinforcement plate 12 is preferably bent in such a manner so as to define an "omega" in sectional view.

The first fixing means 6 is operatively active also on the reinforcement plate 12 to fix the reinforcement plate to the end 4a, 4b of the crossbar 4 and to the upper end 2a, 3a of the corresponding lateral jamb 2, 3.

In the embodiment illustrated in figures 8 and 9, the second fixing means 7 comprises a further reinforcement bracket 16 of the assembly.

The characteristics of the frame for a landing door of an elevator according to the present invention emerge clearly from the above description, as do the advantages.

In particular, the proposed frame can be used for different sizes of the opening of the door.

In fact, depending on the width of the opening to be covered, it is possible to set the mutual position of the lateral jambs and crossbar. The variation of the width of the opening is guaranteed by:

- sliding of the crossbar inside the recesses obtained in the upper ends of the lateral jambs;

- elongated through slots obtained in the upper ends of the lateral jambs (or in the crossbar), which allow "continuous" variation of the position of the crossbar, or through holes obtained in the upper ends of the lateral jambs (or of the crossbar), which allow a "fair" variation of the position of the crossbar.

Depending on the height of the opening to be covered, it is possible to set the height of the sill owing to the through holes obtained in the lower ends of the lateral jambs, to which the sill support bracket is fixed.

In this manner, frame manufacturing is simplified and requires only three types of piece in the warehouse. In fact, the opening is varied owing to the crossbar/lateral jambs and sill/ lateral jambs sliding mechanisms.