[0001] The present invention refers to a reprogrammable lock which makes it possible, through
rotation of the rotor by means of special reprogrammable keys, to modify the key reading
mechanism, thus allowing the lock to operate with keys which have different codes
from those used previously and thus preventing the latter from operating the lock.
[0002] Reprogrammable locks are known to the art which in any case present some drawbacks,
such as for example structural complexity, difficult industrial production, complicated
reprogramming operations, and poor safety and reliability.
[0003] A first object of this invention is to produce a reprogrammable lock that can be
produced industrially.
[0004] Another object of the invention is to produce a reprogrammable lock that has particular
features of mechanical strength and resistance to attempts at picking.
[0005] Another object is to provide a lock that can be reprogrammed with rapid, safe operations
by the user.
[0006] Yet another object of the invention is to produce a reprogrammable lock that can
be programmed only by those holding special programming keys.
[0007] These objects are achieved in accordance with the invention with the characteristics
listed in appended independent claim 1.
[0008] Advantageous embodiments of the invention are apparent from the dependent claims.
[0009] The reprogrammable lock according to the invention comprises:
- a stator in the form of a hollow cylinder,
- a rotor in the form of a cylindrical block mounted rotatably inside the stator, and
- a locking and programming mechanism disposed inside the rotor.
[0010] The locking and programming mechanism comprises:
- a plurality of key reading plates disposed transversally inside the rotor and provided
with slots disposed in register with each other to allow the passage of a user or
programming key whose coding profile defines the movement of said key-reading plates,
- a plurality of locking plates mounted transversally in said rotor and provided with
an end that protrudes outward from the rotor to engage in a cavity defined inside
said stator so as to block rotation of the rotor with respect to the stator, said
locking plates being able to couple with said key-reading plates so as to be able
to be moved into an unlocking position to allow rotation of the rotor with respect
to the stator,
- at least two lateral inserts destined to be disposed transversally in said rotor,
integral with the locking plates and provided with an arched surface adapted to slide
on the inner surface of the stator, and
- a rotation stop plate disposed transversally inside said rotor and provided with a
slot disposed in register with the slots of said key reading plates to allow the passage
of the key, and having one end that protrudes outward from the rotor to engage in
a cavity defined inside said stator so as to block rotation of the rotor with respect
to the stator.
[0011] Further characteristics of the invention will be made clearer by the detailed description
that follows, referring to a purely exemplifying and therefore non limiting embodiment
thereof, illustrated in the appended drawings, in which:
Figure 1 is a perspective view, illustrating all the members of the reprogrammable
lock according to the invention exploded;
Figures 2 and 2A are two cross sectional views of the assembled lock according to
the invention, taken respectively along the plane of a rotation stopping plate and
of a key reading plate, in which the lock is in the initial state as supplied;
Figures 3 and 3A are two views like Figures 2 and 2A, in which the programming key
has been inserted into the lock;
Figures 4 and 4A are two views like Figures 2 and 2A, in which the rotor has been
turned 45° to carry out programming of the lock;
Figures 5 and 5A are two views like Figures 2 and 2A, in which the programming key
has been removed once programming has been carried out;
Figures 6 and 6A are two views like Figures 2 and 2A, in which the user key has been
inserted into the lock;
Figures 7 and 7A are two views like Figures 2 and 2A, in which the rotor has been
rotated 180° with respect to the situation illustrated in Figures 6 and 6A.
[0012] A reprogrammable lock according to the invention is described with the aid of the
figures. Figure 1 shows the reprogrammable lock according to the invention, with all
its details exploded.
[0013] The lock comprises a stator 1, with a substantially hollow cylindrical shape, provided
with an axial hole 1a to contain a rotor 2 in the form of a small cylinder that can
rotate inside the stator 1.
[0014] In the inside surface of the stator 1, inside the hole 1a, cavities 1c (four like
opposed cavities) and 1b are defined, adapted to be used to house the members of the
lock mounted in the rotor 2 as will be described hereunder.
[0015] The rotor 2 is composed of a cylindrical body wherein are formed cavities which contain
the various members of the reprogramming mechanism of the lock. For this purpose transverse
cavities 2b are formed on the side surface of the rotor 2, adapted to receive respective
key reading plates 3 and respective springs 12 which bias the key reading plates 3
radially outward. To be precise, a first group of four key reading plates 3 is inserted
in a first row of transverse slots 2b and a second group of five key reading plates
3 is inserted in a second row of transverse slots 2a disposed in an opposite position
to the first row.
[0016] Again in the lateral surface of the rotor 2, near the ends thereof, two transverse
seats 2f are formed, adapted to house lateral inserts 6 with respective springs 13
which bias the lateral inserts 6 radially outward.
[0017] Again in the lateral surface of the rotor 2, between the two rows of seats 2b, there
is a row of transverse seats 2a adapted to receive respective locking plates 4. To
be precise, nine locking plates 4 are provided, that is to say a number equal to the
number of key reading plates 3. Each locking plate 4 receives a respective programming
plate 5 adapted to couple with a respective key reading plate 3, as will be described
hereunder.
[0018] In the lateral surface of the rotor 2, near the front end thereof, a last transverse
cavity 2c is provided, which serves to contain a rotation stop plate 10 and the spring
thereof 12 which biases it radially outward.
[0019] In the front part of the rotor 2 there is a first longitudinal cavity 2d which serves
to receive a user key 8 or a programming key 9, as will be described hereunder.
[0020] Again in the front part of the rotor 2 there is a second longitudinal cavity 2e which
serves for insertion of a pin 7 which is used to join the locking plates 4, the programming
plates 5, the lateral inserts 6 and the respective springs 13 in a single body.
[0021] The key reading plates 3 have a shaped cavity 3a with a protruding tooth 3c which
serves for the passage and reading of the coding profile 8b, 9b present on the keys
8, 9.
[0022] The outer part of each key reading plate 3 has teeth 3b which couple with matching
teeth 5a provided on the outer part of each programming plate 5. In this manner, the
key reading plates 3 and the programming plates 5 form a single group, thus determining
coding. The key reading plates 3 never protrude beyond the edge of the outer diameter
of the rotor 2, and their function is solely that of adapting to the coding profile
8b, 9b produced on the key 8, 9, without interfering with rotation of the rotor 2
with respect to the stator 1.
[0023] The bottom part of each key reading plate 3 has an undercut seat 3d where the respective
spring 12 is housed.
[0024] The locking plates 4 have a seat 4a which serves to contain the programming plates
5. In the locking plates 4 there is furthermore a slot or hole 4b which serves for
passage of the pin 7. The locking plates 4 have one end which protrudes outward from
the rotor 2 entering into the cavity 1c of the stator 1 to block rotation of the rotor
2 if an unauthorized person attempts to open the lock with a key with different coding
from that of programming or use.
[0025] The programming plates 5 have teeth 5a which engage with the teeth 3b of the key
reading plates 3 which determine coding of the user key during programming. The programming
plates 5 have a slot or hole 5b to receive the pin 7 so as to form a single body integral
with the locking plates 4 and key reading plates 3.
[0026] The lateral inserts 6 have an arched surface 6b adapted to slide on the inside surface
of the stator 1. The inside surface of the stator acts as a cam, whereas the arched
surface 6b of the lateral inserts 6 acts as a cam follower.
[0027] The lateral inserts 6 further comprise a hole 6a for insertion of the pin 7 and another
blind hole (not shown) which contains the respective springs 13. The lateral inserts
6 thus serve to move the programming plates 5 integrally with the key reading plates
3.
[0028] The front rotation stopping plates 10 have a seat 10a adapted to allow the user key
8 or the programming key 9 to pass therein. The end of the rotation stopping plate
10 protrudes from the rotor 2 to engage partially in the cavity 1c of the stator 1
and block rotation of the rotor. The rotation stopping plate 10 is also used as an
anti-picking plate, in that it is made of a material that withstands attempts at drilling
or forcing with blunt instruments. In the outer part of the rotation stopping plate
10 there is a relief cut 10b which provides a housing for the spring 12.
[0029] A rotation limiter 11 consisting of a circular plate which has a square hole 11a
and a tooth 11b is disposed in the rear part of the rotor 2. The rotation limiter
11 is applied in the rear part of the rotor 2 to limit rotation of the rotor during
90° opening of the lock.
[0030] In the front part of the rotor 2 is disposed a hood 14 which has in its front part
a cavity 14a destined to be disposed in register with the cavity 2d for passage of
the user key 8 or of the programming key 9.
[0031] The lock according to the invention is supplied with two keys 8 and 9, with coding
profiles 8a and 8b identical to each other. These are reversible keys with a two-track
inner profile. One is the programming key 9 and the other is the user key 8.
[0032] The programming key 9 differs from the user key 8 in that it has two teeth 9a and
relative relief cuts formed at the end of the shank of the coding plane 9b, at the
shoulder of the key. The teeth 9a of the programming key serve to operate the rotation
stopping plate 10, which is the first plate in the rotor 2, in the direction of insertion
of the key.
[0033] Operation of the lock according to the invention, which takes place by means of a
sequence of operations, is described hereunder with reference to Figures 2-7A.
[0034] The assembled lock, in the state in which it is supplied to the client, is as illustrated
in Figures 2 and 2A. As shown in Figure 2, the rotation stopping plate 10 is locked
in the cavity 1b of the stator 1, preventing rotation of the rotor 2 with respect
to the stator 1 in both a clockwise and a counterclockwise direction. The lateral
insert 6 is disposed in the cavity 1c of the stator 1 and prevents rotation of the
rotor only in a counterclockwise direction. As shown in Figure 2A, the teeth 3b of
the key reading plates 3 are opposed to the teeth 5a of the programming plates 5,
that is to say they are misaligned with respect to the grooves defined by the teeth
5a of the programming plates 5.
[0035] This condition is called the programming condition because in this position the lock
must be programmed, giving the lock a missing characteristic, namely the ability to
read only a key coding, so that it is used univocally by the owner of the programming
key. From this position, the special programming key 9 must be inserted into the slot
2d of the rotor 2 in order to be able to programme the lock.
[0036] As shown in Fig. 3, once the programming key 9 has been inserted into the lock, the
teeth 9a of the programming key 9 move the rotation stopping plate 10 from the cavity
1b of the stator 1, so that the whole rotor assembly 2 can subsequently rotate to
the position in which programming has been accomplished, that is, 45° clockwise with
reference to the figures. Before proceeding with rotation of the rotor 2, it should
be noted that the rotor 2 is unable to rotate counterclockwise because of the lateral
insert 6 which abuts against a plane of the cavity 1c of the stator 1, as shown in
Figures 2 and 3.
[0037] Furthermore, with insertion of the programming key 9, Figure 3A the key reading plates
3, thanks to the bias of the relative springs 12, come to rest on the coding profile
9b of the programming key 9, correct alignment between the teeth 3b of key reading
plates 3 and the grooves defined between the teeth 5a of the programming plates 5
thus taking place.
[0038] As shown in Figure 4, during programming (45° rotation of the rotor 2) the curved
surfaces 6b of the lateral inserts 6 slide along a curve 1d defined in the inner surface
of the stator 1 which is eccentric to the axis of the lock. Consequently the lateral
inserts 6 move towards the centre of the rotor 2.
[0039] During this operation, the lateral inserts 6, by means of the pin 7, pull the programming
plates 5 (Figure 4A) inserted in the seat 4a formed in the locking plates 4, until
they couple with the key reading plates 3. In this manner, through meshing of the
teeth 3b and 5a of the key reading plates 3 and the programming plates 5, an integral
assembly is created between the key reading plates 3, the locking plates 4 and the
programming plates 5.
[0040] Once programming of the lock is completed, the rotor 2 is unable to continue its
rotation beyond 45°, in that, as shown in Figure 4, the rotation stopping plate 10
abuts against a plane of the cavity 1c present in the stator 1.
[0041] The next stage will be that of withdrawing the programming key 9 and inserting the
user key 8 with coding 8a identical to the previous one 9a.
[0042] As shown in Figures 5 and 5A, in the situation of the lock being closed without the
key inserted, it is impossible for the rotor 2 to make any type of rotation. In fact,
the rotation stopping plate 10 and the locking plate 4, being part of the integral
assembly of plates 3, 4, and 5 previously described, through the bias of their springs
12, position themselves in the cavity 1c of the stator 1.
[0043] Figures 6 and 6A show the situation in which the user key 8 is inserted in the slot
2d of the rotor. With reference to Figure 6A, during this operation the key reading
plates 3 rest on the coding profile 8a of the key 8. As a result the assembly of plates
3, 4 and 5 moves integrally, aligning itself externally to the outside diameter of
the rotor 2, so as to allow 180° rotation thereof, as shown in Figure 7A.
[0044] With reference to Fig. 6, in the same situation, the rotation stopping plate 10,
through the spring 12 which biases it, comes to rest on the user key 8, which is lower
in its working section than the programming key 9. Because of this the rotation stopping
plate 10 is caused to be moved towards the centre of the rotor 2.
[0045] This causes alignment of the rotation stopping plate 10 with the rotor 2 in the upper
part, whereas in the lower part the rotation stopping plate 10 will abut against an
outer wall 1e of one of the cavities 1c present in the stator 1.
[0046] In this condition the rotor can freely rotate 180°clockwise, as shown in Figure 7.
[0047] The rotation stop at 180° is formed at the shoulder of the rotor 2 which abuts against
a wall If of the cavity 1c.
[0048] In this position, called the "lock open" position, the key 8 can be withdrawn.
[0049] It should be specified that withdrawal and insertion of the keys 8, 9 is determined
by the condition which gives the locking plates 4 the possibility of being able to
protrude from the line of the outside diameter of the rotor 2. In fact the codes 8b
and 9b produced on the keys are of different heights, and are read by the key reading
plates 3, integral with the locking plates 4 and the programming plates 5. Thus during
linear movement of the key 8, 9, a movement of the integral group of plates 3, 4 and
5 is caused which is possible only in the 0° and 180° positions, coinciding with the
cavities 1c formed in the stator 1.
[0050] Moreover, when the user key 8 inserted does not have the same coding as the programming
key 9 (typical in attempts at breaking in with the use of forged keys) the no key
situation described with reference to Figures 5 and 5A is recreated. The differences
in coding between the two keys 8 and 9 mean that a part of the locking plates 4 are
positioned inside the cavity 1c of the stator 1, thus preventing normal operation
of the lock.
[0051] Numerous variations and modifications of detail within the reach of a person skilled
in the art can be made to the present embodiment of the invention without thereby
departing from the scope of the invention as set forth in the appended claims.
1. A reprogrammable lock comprising:
- a stator (1) in the form of a hollow cylinder,
- a rotor (2) in the form of a cylindrical block mounted rotatably inside the stator
(1),
- a plurality of key reading plates (3) disposed transversally inside the rotor (2)
and provided with slots (3a) disposed in register with one another to allow the passage
of a user key or a programming key (8, 9) whose coding profile (8b, 9b) defines the
movement of said key reading plates (3),
- a plurality of locking plates (4) mounted transversally in said rotor (2) and provided
with one end which protrudes outward from the rotor (2) to engage in a cavity (1c)
defined inside said stator (1) so as to block rotation of the rotor (2) with respect
to the stator (1), said locking plates (4) being able to couple with said key reading
plates (3) so as to be able to be moved into an unlocking position to allow rotation
of the rotor with respect to the stator,
- at least two lateral inserts (6) destined to be disposed transversally in said rotor
(2) integral with the locking plates (4), said lateral inserts (6) being provided
with an arched surface (6b) adapted to slide on the inner surface of the stator (1),
and
- a rotation stopping plate (10) disposed transversally inside said rotor (2) and
provided with a slot (10a) disposed in register with the slots (3a) of said key reading
plates to allow the passage of the key (8, 9), said rotation locking plate (10) being
provided with an end which protrudes outward from the rotor (2) to engage in a cavity
(1c) defined inside said stator (1) so as to block the rotation of the rotor (2) with
respect to the stator (1) and being adapted to be operated only by the programming
key (9) to unlock rotation of the rotor with respect to the stator.
2. A reprogrammable lock according to claim 1, characterised in that each locking plate (4) has a seat (4a) adapted to receive a programming plate (5)
that can couple with a respective key reading plate (3).
3. A reprogrammable plate according to claim 2, characterised in that said locking plates (4), said programming plates (5) and said lateral inserts (6)
have respective holes or slots (4b, 5b, 6a) aligned to receive a pin (7) so as to
form an integral assembly.
4. A reprogrammable lock according to claim 2 or 3, characterized in that said key reading plates (3) have outer teeth (3b) adapted to couple in a clamping
relationship with matching outer teeth (5a) formed in said programming plates (5).
5. A reprogrammable lock according to any one of the preceding claims, characterised in that each key reading plate (3) has an undercut seat (3d) adapted to receive a spring
(12) which is interposed between the key reading plate (3) and the rotor (2).
6. A reprogrammable lock according to any one of the preceding claims, characterised in that said rotation stopping plate (10) has a relief cut (10b) adapted to receive a spring
(12) which is interposed between the rotation stopping plate (10) and the rotor (2).
7. A reprogrammable lock according to any one of the preceding claims, characterised in that each lateral insert (6) has a hole in the wall opposite its curved wall (6b) to receive
a spring (13) which is interposed between the lateral insert (6) and the rotor (2).
8. A reprogrammable lock according to any one of the preceding claims,
characterised in that said rotor (2) comprises:
- two opposed rows of transverse seats (2b) to receive said key reading plates (3),
- a row of transverse seats (2a) to receive said locking plates (4),
- two transverse seats (2f) disposed near the side ends to receive said lateral inserts
(6),
- a transverse seat (2c) to receive said rotation blocking plate (10), and
- a longitudinal slot (2d) to allow insertion of the user key or the programming key
(8, 9).
9. A reprogrammable lock according to claim 8, when it is dependent on claim 3, characterised in that said rotor comprises a longitudinal hole or slot (2e) adapted to allow the passage
of said pin (7) which constrains the locking plates (4), the programming plates (5)
and the lateral inserts (6).
10. A reprogrammable lock according to any one of the preceding claims, characterised in that said stator (1) has in its inner surface four diametrically opposed seats (1c) to
receive the end of said locking plates (4) and of said rotation stopping plate (10)
and a seat (1b) to receive said arched surface (6b) of said lateral inserts (6).