The present invention relates to a lock for a double leaf door, which is also adapted to function on double-leaf doors provided with emergency opening devices (handles or emergency door bars).

Leaf doors are usually provided with locks in which a spring latch and at least one sliding latch protrude from the door edge, and are designed to engage in respective recesses of the jamb in order to ensure the closure. The spring latch can usually be retracted with the movement of the handle or with a turn of the key in the actuation cylinder. The spring latch is actuated by the movement of the cylinder that is functionally associated with the key.

In double leaf doors, the secondary leaf can be locked manually (with adapted locking couplings that are generally mounted on the ceiling and floor) or it can be, like the main leaf, opened by way of a respective handle (in such case the handle will be designed to retract the locking couplings, if present). Obviously the handle of the secondary leaf will not be operational when the main leaf is closed (in particular if it is locked) in order to prevent forced entry.

For emergency doors, however, the spring latch and the sliding latch (even when the latter is completely extracted for secure closure) must be completely retracted with a single movement of the handle (or of the panic bar): a person fleeing (from a fire or other risk situations) must be able to exit from the spaces delimited by the door simply by pushing the handle (or the panic bar).

In double leaf doors the safety lock is provided with a pusher that acts on a protruding pin of the lock, freeing the reentry of the sliding latch and of the spring latch: at this point the action of a pusher (in general the same one) on the sliding latch causes its retraction and, thanks to adapted internal lever mechanisms, also causes the consequent retraction of the spring latch, and thus the opening of the main leaf as well.

Such pin, according to a particularly efficient embodiment devised by the applicant and disclosed in Italian patent ITO 1263073, is installed at the end front wall of the sliding latch: this embodiment ensures that it is not accessible (for the purposes of forcing entry) and thus makes it possible to maintain a high level of security for the lock that comprises it.

The conventional implementation solutions have a great many mechanical linkages, which are interposed between the protruding pin and the closing elements (i.e. the sliding latch and the spring latch), and which can excessively increase the force to be applied on the pin in order to allow the opening (making its correct and secure actuation difficult), and which are subject to the behavior of delicate mechanical components (such as springs and elastic means in general).

The aim of the present invention is to solve the above mentioned drawbacks, by providing a lock for leaf doors which is mechanically simple and easy to actuate.

Within this aim, an object of the invention is to provide a lock for leaf doors which does not necessarily require the presence of delicate components, such as springs and elastic means.

Another object of the present invention is to provide a lock for leaf doors which is low cost, easily and practically implemented and safely applied.

This aim and these and other objects which will become better apparent hereinafter are achieved by a lock for leaf doors of the type comprising a box-like body for containing a movement cylinder associated with a respective actuation key, a rotating bushing associated with a handle, adapted lever mechanisms for the translation of at least one spring latch and of at least one sliding latch, which are functionally associated with said handle and said cylinder, and a tab protruding from said sliding latch, said at least one sliding latch being locked in the extracted configuration when said tab is protruding, and being free to retract if subjected to an external force, when said tab is retracted inside said sliding latch following a respective external action, characterized in that said sliding latch comprises an internal cavity for the slideable accommodation of a lever that is constituted, at a first end thereof, by said tab, and, at a second end thereof, by a tooth, said tooth facing toward an arm of a cam that is pivoted to said box-like body, a second arm of said cam resting against a protrusion of an element for the movement of said sliding latch, said movement element comprising a projection that can slide within a groove of said sliding latch, said groove being provided with an inclined portion and with an offset recess for the accommodation of said projection in the locked configuration of said sliding latch, the retraction of said tab causing the forcing of said tooth on said arm, with consequent rotation of said cam and lifting of said arm, thus translating said movement element by means of said protrusion, the translation of said movement element causing the egress of said projection from said offset recess of said groove with consequent free retraction of said sliding latch, and of said spring latch which is mechanically coupled thereto, following an external force applied to said sliding latch.

Further characteristics and advantages of the invention will become better apparent from the detailed description that follows of a preferred, but not exclusive, embodiment of the lock for leaf doors according to the invention, which is illustrated by way of non-limiting example in the accompanying drawings, wherein:

- Figure 1 is an exploded perspective view of a lock for leaf doors according to the invention;

- Figure 2 is a cross-sectional side view, taken along a central vertical plane, of the lock in Figure 1.

With reference to the figures, a lock for leaf doors is generally designated by the reference numeral 1.

The lock 1 according to the invention comprises a boxlike body 2 for containing a movement cylinder 3 (in the accompanying figure the reference numeral 3 shows only a portion of the entire cylinder) which is associated with a respective actuation key, a rotating bushing 4 associated with a handle, and adapted lever mechanisms 5 for the translation of at least one spring latch 6 and of at least one sliding latch 7 (which can slide into an opening 9 of the boxlike body 2).

The spring latch 6 and the sliding latch 7 are functionally associated with the handle and with the cylinder 3.

The lock 1 further comprises a tab 9 that protrudes from the sliding latch 7.

The at least one sliding latch 7 is locked in the extracted configuration when the tab 9 is protruding; the sliding latch 7 on the other hand is free to retract, when it is subjected to an external force that forces its retraction, only when the tab 9 is retracted inside the sliding latch 7 following a respective external action.

In the lock 1 according to the invention the sliding latch 7 comprises an internal cavity 7a for the slideable accommodation of a lever 10 that is constituted, at a first end thereof, by the tab 9, and, at a second end thereof, by a tooth 1 1.

The tooth 11 is facing toward an arm 12 of a cam 13 that is pivoted to the box-like body 2.

A second arm 14 of the cam 13 is resting against a protrusion 15 of a movement element 16 intended for the translation of the sliding latch 7 (and also of the spring latch 6).

The movement element 16 comprises at one of its ends 17 a projection 18 that can slide into a groove 19 of the sliding latch 7 (when the lock 1 is completely mounted and in the condition for use).

The groove 19 is provided with an inclined portion 20 and an offset recess 21.

The offset recess 21 is adapted to accommodate the projection 18 in the locked configuration of the sliding latch 7: in such condition, even by exerting a force on the sliding latch 7 so as to force it to retract, the sliding latch 7 cannot retract because the pin 18 will be forced to rest against the side walls of the offset recess 21.

The retraction of the tab 9 causes the forcing of the tooth 11 on the arm 12, with consequent rotation of the cam 13 (according to the illustrative embodiment shown in the accompanying figures the rotation of the cam 13 upon a retraction of the tab 9 is anticlockwise) and lifting of the arm 14.

The lifting of the arm 14 causes the translation of the movement element 16 (again with reference to the illustrative embodiments shown in the figures, the movement element 16 will be subjected to lifting) entrained by the protrusion 15.

In turn, the translation of the movement element 16 causes the egress of the projection 18 from the offset recess 20 of the groove 19.

Such egress causes the movement of the projection 18 in the inclined portion 20, with consequent free retraction of the sliding latch 7, and of the spring latch 6 which is mechanically coupled thereto, following an external force applied to the sliding latch.

The force applied to the tab 9 (and thus to all of the lever 10) and the force applied to the sliding latch 7 can thus be constituted by the action of the panic bar installed on the secondary leaf onto which the main leaf, on which the lock 1 is installed, is closed.

By acting thus on the panic bar of the secondary leaf, in addition to causing the retraction of the door bolts that are present on it, the activation will also be caused of a pusher that acts on the sliding latch 7 and on the tab 9 of the lever 10, pushing them to re-enter the respective seats (i.e. making them retract).

Specifically the pressure exerted on the tab 9 causes the release of the sliding latch 7 (egress of the projection 18 from the offset recess 21 and its alignment with the inclined portion 20 of the groove 19) and thus a subsequent pressure exerted on the sliding latch 7 will enable its retraction.

The lever 10 is flattened and substantially rectangular. The first end of the lever 10, which comprises the tab 9, is not as high as the remaining part of the lever 10 and the second end comprises the tooth 1 1 that protrudes along an inclined direction with respect to the longitudinal direction of the lever 10.

According to a particularly efficient embodiment that offers optimal operation, the tooth 11 has a rounded end shape for continuous abutment on the arm 12 of the cam 13.

Thus the abutment of the tooth 1 1 on the arm 12 will occur along the rounded outline of the tooth proper and will ensure a continuity of contact during the movement, thus avoiding bounces or clicks in the rotation of the cam 13 which may prejudice the correct operation of the entire kinematic chain associated with it.

According to an embodiment of undoubted applicative interest, the cam 13 can effectively have two walls that are mutually opposite and mutually inclined so as to define an angle.

According to such embodiment, the cam can thus have a substantially triangular shape, even though the possibility is not excluded of having different shapes that in any case allow the two walls to be mutually opposite and incident.

Such walls are constituted by the outer sides of the first arm 12 and of the second arm 14.

The cam 13 is thus pivoted on the boxlike body 2 proximate to the vertex of the angle defined by the walls.

With reference to the accompanying figures, the cam 13 is coupled to the boxlike body 2 at the pin 13 a.

The movement element 16, according to an embodiment of undoubted practical application, comprises a first laminar band 22 that is provided, proximate to its end face 23, with the protrusion 15, and, at a central portion thereof, with a first toothing 24 that is functionally associated with a gear 25 for controlling the spring latch 6. The gear 25 can preferably be constituted by a circular sector that is toothed at one of its ends and pivoted to the boxlike body at an intermediate portion thereof, and having the opposite end with respect to the toothed end associated with the rotating bushing 4 (which is intended to accommodate the handle): a rotation of the gear 25 thus causes a rotation of the bushing 4 (similar to the rotation that occurs by rotating the handle) with consequent retraction of the spring latch 6.

In such embodiment, the movement element 16 can further positively comprise a second laminar band 26, facing toward the first band 22, provided with a second toothing 27 that is functionally associated with a toothed wheel 28 that is coupled to a toothed bar 29 for controlling the spring latch 6.

In this case also, the toothed bar 29 is associated with the rotating bushing 4 (which is designed to accommodate the handle): a rotation of the toothed wheel 28 causes a translation of the bar 29 which is followed by a rotation of the bushing 4 (similar to the rotation that occurs by rotating the handle) with consequent retraction of the spring latch 6.

It should further be noted that the second laminar band 26, upstream of the respective second toothing 27, comprises a contoured bump 30.

The toothed wheel 28 also comprises, as a consequence, a cavity 31 of shape and dimensions that are complementary to those of the bump 30 for the stable accommodation thereof in the closed configuration of the leaf, i.e. when the sliding latch 7 and the spring latch 6 are protruding from the boxlike body 2 and the tab 9 is protruding from the sliding latch 7.

It should further be noted that the projection 18 is arranged on a portion of one of the bands 22 and 26 which faces and is proximate to the groove 19 of the sliding latch 7.

In particular the projection 18 is arranged on the inner face of the second laminar band 26, with reference to the embodiment shown by way of example in the accompanying figures. The offset recess 21 of the groove 19 is preferably constituted by an indentation having a direction perpendicular to the direction of translation of the sliding latch 7.

The recess 21 is thus connected, continuously and at its end region, to the inclined portion 20 of the groove 19.

The groove 19, constituted by the non-aligned succession of the inclined portion 20 and of the recess 21, thus constitutes a desmodromic cam for guiding the projection 18.

It should further be noted that, in many cases, the locks fitted to main leaves and to secondary leaves comprise door bolts that are intended to engage respective seats of the jamb (or of the masonry doorway) which are arranged above and below the leaf proper (when this is in the closed configuration).

It should be noted that, in such case, the movement element 16 will be coupled, with one of its ends 32, to a first door bolt that selectively protrudes from the lower end of the installation leaf.

In such an implementation, the toothed bar 29, for controlling the spring latch 6, can be coupled, with an end 33 thereof, to a second door bolt that selectively protrudes from the upper end of the installation leaf.

The translational movements of the movement element 16 and of the toothed bar 29 (imposed by the retraction of the sliding latch 7, owing to the action of a pusher of the secondary leaf on the tab 9, in a first, release step, and on the sliding latch 7, in a second, opening step) will also cause the retraction of the lower door bolt and of the upper door bolt, thus enabling the easy opening of the main leaf even if the pressure on the panic bar has been exerted on the secondary leaf only.

Advantageously the present invention solves the above mentioned problems, by providing a lock 1 for leaf doors which is mechanically simple and easy to actuate.

Conveniently, the lock 1 does not necessarily require the presence of delicate components, such as springs and elastic means: in fact it takes advantage of the weight of the various components (and of the influence of the force of gravity) in order to ensure the appropriate certainty of closure (in conditions of standard use) and the certain and immediate opening in the event of actuation of the panic bar in order to allow a rapid and easy flight.

Conveniently the lock 1 for leaf doors can be easily provided while sustaining low costs, and this will result in the undoubted application thereof.

The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

In the embodiments illustrated, individual characteristics shown in relation to specific examples may in reality be interchanged with other, different characteristics, existing in other embodiments.

In practice, the materials employed, as well as the dimensions, may be any according to requirements and to the state of the art.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.