EP3156571A1

EP3156571A1 - Lock with actuation system of the latch bolt

Info

Publication number: EP3156571A1
Application number: EP16192806.4A
Authority: EP
Inventors: Alessandro CAMPLANI
Original assignee: OMEC Serrature SpA
Current assignee: OMEC SERRATURE SpA
Priority date: 2015-10-15
Filing date: 2016-10-07
Publication date: 2017-04-19
Anticipated expiration: 2036-10-07
Also published as: EP3156571B1; HRP20201712T1; RU2664648C2; SI3156571T1; ITUB20154686A1; RU2016139967A

Abstract

Lock (1) for doors and windows, comprising an actuation system (2) of a latch bolt (3), wherein the actuation system comprises:
- a rotatable lever (4) for the translation of the latch bolt from an advanced position to a retracted position,
- a first rotatable wheel (5) arranged coaxially to said rotatable lever,
- coupling means (6) interposed between said first rotatable wheel and said rotatable lever and adapted to transfer a rotary motion from said first rotatable wheel to said rotatable lever, and
- a member (7) coupled to said first rotatable wheel for rotating said first rotatable wheel.

Description

The present invention relates to a lock comprising an actuation system of a latch bolt, for example a multipoint lock with translatable bolt.
Multipoint locks with translatable bolt are known, which comprise a main translatable bolt and a system for transmitting the movement of the main bolt to secondary bolts for secure closing of the window or door at multiple points.
For example, patent document WO 2011/051086 A2 discloses a multipoint lock with translatable bolt comprising a rotating distributor equipped with transformation means of its own rotational movement into a first reversible translation of the bolt from a retracted position to an extracted position relative to the lock box and into a second reversible translation of a control lever of the latch bolt of the lock.
Also windows and doors locks are known, comprising electric actuating systems of the latch bolt.
For example, electric actuating systems of the latch bolt exist that comprise a small piston for recharging a spring which triggers the latch bolt using an electromagnet.
The Applicant considers that the actuating systems of the latch bolt used in known locks are not devoid of drawbacks, and they can be improved in many aspects.
For example, the Applicant discovered that the actuating system of the latch bolt through a key described in WO 2011/051086 A2 is structurally complex and/or generates friction forces which counteract the movement of the latch bolt by the key, these friction forces requiring the application of a greater rotation torque on the key by the user.
For example, in WO 2011/051086 A2 the control lever of the latch bolt during its translational movement caused by the rotating distributor slides along the end wall of the lock box, generating a friction force which counteracts the movement. Besides, the coupling by contact between the rotating distributor and the control lever and/or between the control lever and the rotating lever retracting the latch bolt causes sliding between the two contact surfaces, with related friction.
Moreover, according to the Applicant the electric actuating systems of the latch bolt used in the known locks require high number of components and are structurally very complex.
Therefore, the Applicant has faced the problem of realizing a lock with an actuation system of the latch bolt which is both structurally simple and/or cheap to build and particularly efficient as regards the forces to be applied onto it to actuate the bolt lock, in terms of intensity of the forces and/or in terms of ease of application of such forces.
The Applicant has solved the above problem with the lock of the present invention as defined in the attached claims and/or in the various embodiments disclosed in the following.
In an aspect the invention relates to a lock for doors and windows comprising an actuation system of a latch bolt.
The actuation system comprises a rotatable lever for the translation of the latch bolt between an advanced position and a retracted position (typically from an advanced position to a retracted position), a first wheel arranged coaxially to said rotatable lever, coupling means interposed between said first wheel and said rotatable lever and adapted to transfer a rotary motion from said first wheel to said rotatable lever, and an actuating member coupled to said first wheel for rotating said first wheel.
The term 'wheel' means an element of the lock (typically circular shaped) able to rotate around an its own rotation axis, typically passing through the element itself.
According to the Applicant the translation (typically the retraction) of the latch bolt by the actuating member which rotates the first wheel, which in turn rotates, by the coupling means, the rotatable lever, which in turn actuates in translation the latch bolt, allows to move the latch bolt efficiently, particularly with reference to the torque to be applied for moving the latch bolt.
For example, in the embodiment of the present invention in which the actuating member is a pinion of an electric motor, or an idler wheel coupled (directly or indirectly) to a pinion of an electric motor, the latch bolt can be moved by the rotation of the pinion with minimal torque required, in face of a structure simple and compact altogether.
In the embodiment of the present invention in which the actuating member is an idler wheel actuatable by the cam of a lock cylinder using a series of interposed wheels mutually coupled, thus avoiding gearing parts which translate sliding, the movement of the latch bolt can occur with a low torque applied by the cam (and thus by the key in user's hand), inasmuch as it is not necessary to overcome the friction forces generated by the sliding between the parts and the torque transfer from a wheel to another is efficient and/or easily tunable at will during design phase.
Preferably said coupling means are adapted to transfer the rotary motion from said first wheel to said rotatable lever selectively, depending on whether they are in a first operating condition, in which they transfer the rotary motion, or in a second operating condition, in which they do not transfer the rotary motion. In this way it is possible to advantageously uncouple the first wheel from the rotatable lever, for example during the actuation of the lock bolt by a gearing shared between the actuation of the latch bolt and the actuation of the bolt (see below).
Preferably said coupling means comprise an eccentric projection integral with one of said first wheel and said rotatable lever, and a circumferentially extending groove obtained in the other of said first wheel and said rotatable lever, the groove being engaged by said projection.
Preferably the groove has a stop for said projection, said first operating condition corresponding to a condition of contact between the projection and the stop and to a rotation of the first wheel that keeps the projection and the stop thrusted against each other, and said second operating condition corresponding to a condition of separation between the projection and the stop.
In this way advantageously, for example in locks with a cylinder, during the rotation of the key in the cylinder for retracting or advancing the bolt, although the first wheel rotates (caused by the gearing made of the series of interposed wheels), that rotation is not transferred to the rotatable lever inasmuch as the projection is free to slide along the circumferentially extending groove in both directions (second operating condition). When the bolt is completely retracted, instead, the projection is in a condition of contact with the stop of the groove, so that a further rotation of the key (first operating condition) corresponds to a rotation of the rotatable lever (now coupled with the first wheel by the contact between the projection and the stop) and a consequent translation of the latch bolt from an advanced position to a retracted position.
Preferably the projection is integral with said first wheel and the groove is formed in said rotatable lever. In this way advantageously sizes are optimized taking advantage of the spaces and the dimensions of the elements, inasmuch it is allowed a reduced width of the first wheel.
Preferably the groove is a through groove. In this way advantageously sizes are reduced and an optimal coupling is obtained.
Preferably said actuating member is a rotating member. In this way, notwithstanding a simple structure, an efficient transmission of motion is realized. In an alternative embodiment of the present invention, said actuating member can be a rod with a respective rack which engages a toothed crown of the first wheel.
In an embodiment the lock comprises an electric motor provided with a pinion (preferably toothed) consisting of said rotatable actuating member or coupled, either directly or indirectly, to said actuating member for rotating said actuating member. In this way it is realized a lock in which the actuation of the latch bolt is done electrically in an efficient way.
Preferably said actuating rotatable member is a second wheel (e.g. an idler wheel). Preferably the lock comprises a third wheel (directly) coupled to said second wheel. Preferably the lock comprises a fourth wheel (directly) coupled to said third wheel. Preferably the lock comprises a fifth wheel (directly) coupled to said fourth wheel and more preferably (directly) actuatable by a cam of a cylinder for locks.
The lock can also comprise said cylinder for locks.
In an embodiment of the present invention, the lock comprises an electric motor provided with a pinion and said fifth wheel coincides with said pinion. In this way advantageously the motor can actuate both the bolt and the latch bolt electrically, instead of, and/or as well as, manually.
Preferably one or more of said wheels (more preferably all of said wheels) and/or said actuating rotatable member and/or said pinion(s) is/are toothed (namely provided with at least one respective toothed crown) and the direct coupling between two wheels/organs is realized by mutual meshing.
In an embodiment the direct coupling between the two wheels/organs is done by friction contact (in this case the toothed crowns are not necessary).
In an embodiment the coupling between two wheels/organs can be indirect by interposition of, or by means of, further elements, such as for example belts or chains.
Preferably the fourth toothed wheel comprises a first toothed crown directly meshed with the fifth toothed wheel and a second toothed crown, coaxial and integral with the first toothed crown, directly meshed with the third toothed wheel. Preferably the second toothed crown has a (much) smaller diameter than a diameter of the first toothed crown. Preferably the second toothed crown is axially displaced with respect to the first toothed crown.
Preferably the first and/or the second and/or the third and/or the fifth toothed wheel present a respective (single) crown, toothed on a peripheral edge.
Preferably the first toothed crown and/or the respective toothed crown of the fifth wheel is/are interrupted for a respective circumferential tract. In this way the cylinder cam during its rotation is housed in the respective interrupted tract. Preferably the lock comprises a translatable bolt coupled directly with said third wheel for receiving a translational motion from the third wheel between an advanced position and a retracted position.
Preferably the third wheel has an eccentric pin engaging a groove formed on said bolt, in order to transform a rotary motion of the third wheel into said translational motion of the bolt.
Preferably the groove has a substantially straight segment and at least a circle arc segment having a radius equal to a radius of the eccentric pin with respect to a rotation axis of the third wheel and centered on the rotation axis of the third wheel, when the bolt is in an advanced position, the segments being continuous one with the other.
Preferably the groove has a (further) circle arc segment having a radius equal to a radius of the eccentric pin with respect to a rotation axis of the third wheel and centered on the rotation axis of the third wheel, when the bolt is in retracted position. In this way advantageously the further circle arc segment allows a small rotation of the third wheel and, consequently, of the second and first wheels and of the rotatable lever (for retracting the latch bolt) without a corresponding translation of the bolt (which is already completely retracted).
Preferably the bolt has a cavity in which is (at least partially) housed said forth wheel, more preferably said first toothed crown.
Preferably the lock comprises a sixth wheel (more preferably toothed) directly coupled to the bolt for receiving a rotary motion from the bolt. Preferably the bolt comprises a respective pin engaged in an eccentric opening of said sixth wheel, the eccentric opening extending radially, in order to transform a translational motion of the bolt into said rotary motion of the sixth wheel.
Preferably the lock comprises two transmission rods provided with a respective rack, wherein the two racks mesh with the sixth toothed wheel on opposite sides of the latter. In this way is advantageously possible to transfer the translational motion of the bolt, which is the main bolt of the lock, to further secondary bolts, for example in multiple point locks.
Preferably the lock comprises a stem on which the latch bolt can be engaged, for example with a thread coupling.
Preferably the rotatable lever comprises a first arm extending (substantially) radially which engages, typically by contact, said stem. Typically, the first arm engages at one of its free ends a flange arranged at a free end of said stem, the first arm being interposed between the flange and the latch bolt. In this way advantageously it is possible to transfer the rotational motion of the rotatable lever into the translational motion of the latch bolt.
Preferably the lock comprises a first spring interposed between said stem and a box-shaped body of the lock, to exert a thrust on said stem towards said advanced position of the latch bolt. In this way advantageously the latch bolt is taken back and/or maintained, lacking any counteracting force, to the advanced position and the rotatable lever is taken back to a corresponding rest position.
Preferably the lock comprises a rotatable body coaxial with said rotatable lever and decoupled from said rotatable lever, the rotatable body being provided with a second arm, distinct from the first arm, extending (substantially) radially, which engages, typically by contact, said stem.
Typically the second arm engages at one of its free ends said flange on the side opposite to the first arm with respect to the stem, the second arm being interposed between the flange and the latch bolt.
Typically the rotatable body is provided with a non-circular through opening for the passage of a shaft of a handle, in order to realize a mechanical coupling between the handle and the rotatable body. In this way advantageously is possible to transfer the rotational motion of the rotatable body, imposed by the manual rotation of the handle, to the translation motion of the latch bolt, in a way independent from the rotation of the rotatable lever.
Preferably the rotatable body comprises a main body, provided with said through opening, and a secondary body provided with said second arm and integrally coupled to the main body. In this way the assembly of the lock is simplified. Preferably the lock comprises a second spring interposed between said rotatable body (typically said main body) and a box-shaped body of the lock, to exert a thrust on said rotatable body towards a rest position. In this way advantageously the handle is taken back and/or maintained, lacking any counteracting force, in the corresponding rest position and the latch bolt can be taken back, by the first spring, in the advanced position.
Preferably the lock comprises a containment box.
Preferably the lock (e.g. the box) comprises a frontal body (typically plate-like), which typically forms a frontal wall, typically equipped with a first through opening for the latch bolt and/or a second through opening for the bolt.
Preferably the lock (e.g. the box) comprises a first and a second lateral body (typically plate-like), which typically forms, at least partially, a first and a second lateral wall and, in an embodiment, an end wall and/or a superior wall and/or a bottom wall.
Typically the lock comprises a first structural block advantageously shaped for housing, at least partially, said fourth and fifth wheel and/or said cylinder.
Typically the lock comprises a second structural block (which can be made in one piece or in two pieces or more) advantageously shaped for housing, at least partially, said first wheel. Typically the lock comprises one or more further blocks to toughen the structure of the lock.
Further features and advantages will be more evident from the detailed description of some embodiments exemplar but not exclusive of a lock according to the present invention. Said description will be exposed in the following with reference to the attached figures, provided only for guidance and therefore not limiting, in which:

figure 1 shows a perspective view of a lock according to the invention;
figure 2 shows a partial exploded of the lock in figure 1;
figure 3 shows a perspective view of the lock in figure 1 with some parts removed and from a different angle;

figure 4 shows the object presented in figure 3 partially exploded;
figure 5 and 6 show, respectively from two different angles, the object of figure 3 further exploded with respect to figure 4 and with some parts removed;
figure 7 shows a rear view of the lock of figure 1 with some parts removed. Referring to figures, with number 1 it is generally indicated a lock for doors and windows according to the present invention.

Even though the exemplar lock shown is a multipoint lock with translating bolt, the present invention applies to all types of lock, with or without bolt, with a single or multiple bolts, manual or electric or motorized, etc.
The lock 1 comprises an actuating system 2 of a latch bolt 3.
The term 'latch bolt' indicates any element able to interact with the jamb of the door or window, for example the traditional latch bolt exemplarily shown or a roller latch bolt.
The actuation system 2 comprises a rotatable lever 4 for translating a latch bolt from an advanced position (shown in figure) to a retracted position, a first wheel 5 arranged coaxially to the rotatable lever and coupling means 6 interposed between the first wheel 5 and the rotatable lever 4 designed to transfer a rotational motion from the first wheel to the rotatable lever.
The actuating system 2 typically further comprises an actuating organ 7 meshed with the first wheel 5 for rotating the first wheel. In the example presented both the wheels and the actuating member are toothed wheels directly meshed two by two. However, the present invention also contemplates the embodiment (not shown) in which the wheels and/or the organ is/are toothless (namely smooth coupling surfaces) and directly coupled one to another by friction contact, or the case in which the wheels and/or the organ are indirectly coupled by means of belts (if smooth) or chains (if toothed).
Typically, all rotatable elements described and/or claimed have the respective rotational axes mutually parallel and, typically, orthogonal to the transitional trajectory of the latch bolt and/or the bolt.
As already noted, even though the embodiment shown refers to a lock with manual actuation of the latch bolt by key (and by handle), nevertheless the present invention finds also an advantageous application in locks (not shown) with electric actuation of the latch bolt.
That type of lock with electric actuation can comprise an electric motor with a toothed pinion as actuating rotatable member or, in a different embodiment, coupled, directly or indirectly (by interposition of one or more toothed wheels), to the actuating member to perform its rotation.
Returning now to manually actuated locks, preferably the actuating organ 7 is a second toothed wheel, as exemplarily shown in figures.
Preferably the lock comprises a third toothed wheel 8 meshed, preferably directly (namely without interposition of further organs), with the second toothed wheel 7. Preferably the lock comprises a fourth toothed wheel 9 directly meshed with the third toothed wheel 8.
Preferably, as shown in figure, the fourth toothed wheel 9 comprises a first toothed crown 9a and a second toothed crown (or pinion) 9b coaxial, integral and axially dislocated, where the diameter of the second toothed wheel 9b is much smaller than the diameter of the first toothed crown 9a. Preferably the third toothed crown 8 is directly meshed with the second toothed crown 9b.
Preferably the lock comprises a fifth toothed wheel 10 directly meshed with the fourth toothed wheel 9 (more preferably with the first toothed crown 9a) and directly actuatable by a cam of a cylinder for locks (not shown, for example of known type).
As exemplarily shown, the first, the second, the third and the fifth toothed wheels have a unique respective toothed crown on a peripheral edge.
Typically the first toothed crown 9a and the respective toothed crown of the fifth toothed wheel 10 are interrupted by a respective circumferential tract (9c,10a) for housing of the cam of the cylinder during its rotation.
Preferably the lock comprises a translatable bolt 11 coupled directly with a third wheel 8 for receiving from the third wheel a translational motion forward-backward. Preferably the third wheel has an eccentric projection 8a which engages a groove 12 made on the bolt, for transferring a rotational motion of the third wheel to a translational motion of the bolt.
Preferably the groove has a substantially straight tract 12a (in which the eccentric projection passes during the translational motion of the bolt) and a circle arc tract 12b with a radius equal to a radius of the eccentric pin with respect to a rotation axis of the third wheel and centered on the rotation axis of the third wheel, when the bolt is in the advanced position. The circle arc tract 12b allows, when the bolt is in the advanced position, the further rotation of the third wheel by a few degrees while keeping the bolt at rest. The eccentric projection 8a in this way moves along the circle arc eventually to a stop.
For example, the groove 12 has a notch 12c which creates a (further) circle arc tract of the groove (substantially oriented along the width of the groove), with a radius equal to a radius of the eccentric pin with respect to a rotation axis of the third wheel and centered on the rotation axis of the third wheel, when the bold is completely retracted. It is observed that the attached figures show the condition in which both the bolt and the latch bolt are retracted.
Preferably the bolt has a cavity 13 in which it is partially housed the fourth wheel 9, more preferably the first toothed crown 9a.
In an embodiment of the present invention, not shown, the lock is of type commonly known as 'motorized' and comprises an electric motor with a pinion (toothed) directly coupled with the fourth wheel 9 (e.g. with the first toothed crown 9a). In this case the fifth wheel and/or the cylinder can be absent, being functionally replaced by the electric motor.
In an embodiment of the present invention, the lock is of multipoint type (as exemplarily shown), where the transitional motion of the bolt 11, which is the main bolt of the lock, is transferred to further secondary bolts (not shown). To this end preferably the lock 1 comprises a sixth toothed wheel 14 directly coupled to the bolt for receiving from the bolt a rotational motion. Preferably the bolt comprises a respective eccentric projection 15 engaged in an eccentric slot 16 of the sixth toothed wheel, the slot having radial extension for transferring the translation motion of the bolt to the rotational motion of the sixth toothed wheel. Preferably the lock comprises two transmission rods 17 with a respective rack 18, where the two racks are meshed with the sixth toothed wheel at the opposite sides of the sixth toothed wheel. In this way the transmission rods receive a respective translational motion form the sixth toothed wheel and can actuate the secondary bolts.
Preferably the lock comprises a stem 20 on which the latch bolt 3 can be plugged, for example by a thread coupling.
Preferably the rotatable lever 4 comprises a first arm 30 having radial extension which engages the stem by contact. Typically, the first arm engages at one of its free ends 31 (properly shaped) a flange 32 at one of the free ends of the stem, the first arm being interposed between the flange and the latch bolt.
Preferably the lock comprises a first spring 33 (in the example it is torsion-like) interposed between the stem (for example on the flange 32) and a box-shaped body of the lock, for exerting a thrust on the stem along the advanced position of the latch bolt.
Preferably the lock comprises a rotatable body 34 coaxial with the rotatable lever 31 and uncoupled with the rotatable lever (namely there isn't a substantial transfer of thrust and/or motion), the rotatable body having a second arm 35, distinct from the first arm, having a radial extension, which engages, typically by contact, the stem.
Typically, the second arm engages at one of its free ends 36 said flange 32 at the opposite side with respect to the first arm relative to the stem, the second arm being interposed between the flange and the latch bolt. Typically, the rotatable body has a through slot 37 not-circular (called 'frame') for housing of a handle shaft (not shown), for realizing a mechanic coupling between handle and rotatable body. Preferably the rotatable body 34 comprises a main body 34a, having said through slot, and a secondary body 34b having said second arm 35 and integrally coupled to the main body (for example by a mechanical joint coupling as shown in figures).
Preferably the lock comprises a second spring 38 (for example compression-like) interposed between the rotatable body 34 (typically the main body 34a) and the box-shaped body of the lock, for exerting a thrust on said rotatable body along a rest position (shown in figure).
Preferably, in an embodiment (as exemplarily shown in figures), the coupling means 6 comprise an eccentric projection 40 (fig. 6) integral with the first toothed wheel 5, and a groove 41 having circumferential extension made in the rotatable lever 4, the groove being engaged by the projection. Preferably the groove has an end 42 for the projection.
In an alternative embodiment, not shown, the projection is integral with the rotatable lever and the groove is obtained in the first toothed wheel 5.
Preferably the groove 41 passes through the whole thickness of the rotatable lever 4 or of the first toothed wheel 5.
Typically, the lock comprises a containment box 50, comprising a frontal plate-like body 51 (which forms a frontal wall), typically with a first through slot 52 for the latch bolt and a second through slot 53 for the bolt.
Exemplarily, the box comprises a first 54 and a second lateral body 55, plate-like, which typically form, at least partially, a first and a second lateral wall, a bottom wall, a top wall and a bottom wall.
Exemplarily, the lock 1 comprises a first structural block 56 suitably shaped for housing, at least partially, the fourth 9 and the fifth toothed wheel 10 and the cylinder, if present.
Exemplarily, the lock comprises a second structural block 57 suitably shaped for housing, at least partially, the first toothed wheel 5 and the rotatable body 34. Typically, the lock comprises one or more further structural blocks 58 to structure and/or tighten the lock itself.

Claims

A lock (1) for doors and windows, comprising an actuation system (2) of a latch bolt (3), wherein the actuation system comprises:
- a rotatable lever (4) for the translation of the latch bolt between an advanced position and a retracted position,

- a first wheel (5) arranged coaxially to said rotatable lever,

- coupling means (6) interposed between said first wheel and said rotatable lever and adapted to transfer a rotary motion from said first wheel to said rotatable lever, and

- an actuating member (7) coupled to said first wheel for rotating said first wheel.
A lock according to claim 1, wherein said coupling means (6) are adapted to transfer the rotary motion from said first wheel to said rotatable lever selectively, depending on whether they are in a first operating condition, in which they transfer the rotary motion, or a second operating condition, in which they do not transfer the rotary motion.
A lock according to claim 1 or 2, wherein said coupling means (6) comprise an eccentric projection (40) integral with one of said first wheel and said rotatable lever, and a circumferentially extending groove (41) obtained in the other of said first wheel and said rotatable lever, the groove being engaged by said projection.
A lock according to claim 2 and 3, wherein the groove has a stop (42) for said projection, said first operating condition corresponding to a condition of contact between the projection and the stop and to a rotation of the first wheel that keeps the projection and the stop thrusted against each other, and said second operating condition corresponding to a condition of separation between the projection and the stop.
A lock according to claim 3 or 4, wherein the projection (40) is integral with said first wheel and the groove (41) is formed in said rotatable lever, and wherein the groove is a through groove.
A lock according to any one of the preceding claims, further comprising an electric motor provided with a pinion consisting of said actuating member or coupled, either directly or indirectly, to said actuating member for rotating said actuating member.
A lock according to any one of the preceding claims, wherein said actuating member is a second wheel and wherein the lock comprises a third wheel (8) coupled to said second wheel, a fourth wheel (9) coupled to said third wheel, a fifth wheel (10) coupled to said fourth wheel and actuatable by a cam of a cylinder for locks, and a translatable bolt (11) directly coupled to said third wheel for receiving a translational motion from the third wheel between a respective advanced position and a respective retracted position, wherein the third wheel has an eccentric pin (8a) engaging a groove (12) formed on said bolt, in order to transform a rotary motion of the third wheel to said translational motion of the bolt, wherein the groove has a substantially straight portion (12a) and an circle arc portion having a radius equal to a radius of the eccentric pin with respect to a rotation axis of the third wheel and centered on the rotation axis of the third wheel, when the bolt is in said retracted position, said first operating condition corresponding to said retracted position of the bolt, and wherein the bolt has a cavity (13) in which said fourth wheel is at least partially housed.
A lock according to any one of the preceding claims, wherein one or more of said wheels and/or said actuating member and/or said pinion is/are toothed, and a direct coupling is realized by mutual meshing.
A lock according to claim 7 or 8, wherein the fourth wheel (9) comprises a first toothed crown (9a) directly meshed with the fifth toothed wheel and a second toothed crown (9b), coaxial, integral with and axially displaced at the first toothed crown, directly meshed with the third toothed wheel, wherein the second toothed crown has a smaller diameter than a diameter of the first toothed crown, and wherein the first and/or second and/or third and/or fifth toothed wheels present a respective single crown, toothed on a peripheral edge.
A lock according to any one of the preceding claims, comprising a sixth toothed wheel (14) directly coupled to the bolt (11) for receiving a rotary motion from the bolt, wherein the bolt comprises a respective pin (15) engaged in an eccentric opening (16) of said sixth toothed wheel, the eccentric opening extending radially, in order to transform a translational motion of the bolt to said rotary motion of the sixth toothed wheel, the lock also comprising two transmission rods (17) provided with a respective rack (18), wherein the two racks mesh with the sixth toothed wheel on opposite sides of the latter.
A lock according to any one of the preceding claims, comprising a stem (20) on which the latch bolt (3) can be engaged, wherein said rotatable lever (4) comprises a first arm (30) extending substantially radially which engages, typically by contact, said stem, wherein the first arm (30) engages at its free end (31) a flange (32) arranged at a free end of said stem, the first arm being interposed between the flange and the latch bolt, and wherein the lock comprises a first spring (33) interposed between said stem and a box-shaped body of the lock, to exert a thrust on said stem towards said advanced position of the latch bolt.
A lock according to claim 11, comprising a rotatable body (34) coaxial with said rotatable lever (4) and decoupled from said rotatable lever, the rotatable body being provided with a second arm (35), distinct from the first arm, extending substantially radially, which engages, typically by contact, said stem, wherein the second arm engages at its free end (36) said flange (32) on the side opposite to the first arm with respect to the stem, the second arm being interposed between the flange and the latch bolt, wherein the rotatable body is provided with a non-circular through opening (37) for the passage of a shaft of a handle, in order to realize a mechanical coupling between the handle and the rotatable body, wherein the rotatable body (34) comprises a main body (34a) provided with said through opening (37), and a secondary body (34b) provided with said second arm and integrally coupled to the main body, and wherein the lock comprises a second spring (38) interposed between said rotatable body and a box-shaped body of the lock, to exert a thrust on said rotatable body towards a rest position of the handle.