CZ2000879A3 - Tumbler lock and key assembly - Google Patents

Abstract

A combination of a disc tumbler lock and a key (8) therefor provided with key-bit means (8b, 8c), the lock including a lock case (1) having therein a lock bolt (3) movable back and forth and provided with a locking pin (4) or the like and a set of tumbler discs (5) movable by turning the key and which are provided with a locking channel arranged to co-operate with the locking pin (4) to control the transfer movements of the lock bolt (3). The locking channel has at least a first (5a) and a second (5b) branch extending transversely relative to the transfer movement of the lock bolt and a third branch (5c) connecting the first and second branches, whereby the key-bit means (8b) of the key has for each tumbler disc a combination surface (8c) which, when the key is turned in the lock, moves the tumbler disc (5) in the direction of the first (5a) and second (5b) branch to select the locking combination. The key-bit means (8b) contains a guide member (8d) which affects the lock bolt (3) so that, in the final stage of the selecting movement of the tumbler disc (5), it guides the locking pin (4) into the third branch (5c) of the locking channel. The third branch (5c) of the locking channel also has at least one guiding means (5f,5g) which is arranged to prevent movement of the locking pin (4) through the third channel (5c) if the combination surface of the key is incorrect.

Description

Tumbler lock and key assembly

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a tumbler lock assembly with disc tumblers and keys, comprising a lock housing and a back and forward movable lock bolt provided with a lock pin or the like, and a tumbler disc assembly having a key channel provided with a locking channel for cooperating with said locking pin for controlling the displacement movements of the lock bolt, and comprising at least a first branch and a second branch disposed transversely with respect to the displaceable movement of the lock bolt, and a third branch connecting them, the key tooth comprising a combination for each tumbler disc a surface which, when turning the key in the lock, moves the tumbler disc in the direction of said first branch and the second branch for selecting the locking combination.

The invention also relates to a key intended for the aforementioned assembly and a corresponding blank of the key.

BACKGROUND OF THE INVENTION

Disc tumbler locks of the type to which the present invention relates are often used as security locks in doors. As the market is expanding, there is a need for a large number of additional «·« · · · · · «·

alternatives for different keys. This can in principle be achieved, for example, by adding a number of tumbler discs or alternatives of a stepwise configuration when milling the combination faces, or a plurality of combination values. However, both the size of the key and the size of the lock must be kept adequate, while reducing the number of milled teeth for their components can cause malfunctions and opening errors.

Also, the possibility to open the lock with a key must be as difficult as possible. The locking channel of the tumbler discs used in such locks traditionally comprises locking branches and a corresponding connecting branch which is straight and which lies in the direction of the displaceable movements of the lock bolt. In such a case, it is sufficient that the tumbler discs are arranged such that the connecting branches in their locking channels are located in the locking pin position to open the lock with a key. Then, the lock bolt can be pushed into its open position if the lock pin moves directly over the branch of the respective locking channel.

In order to prevent the possibility of the lock being opened by a key, it is known to provide the locking branches of the locking channel with various recesses in which the locking pin can be fastened to the correct position of the tumbler discs. As a result, detecting the position of the tumbler discs can be at least much more difficult.

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SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is an object of the present invention to provide a new tumbler lock and key assembly that allows for a large number of new key alternatives and by means of which the possibility to open the lock by a key lock is much more secure than previously.

The above object has been achieved in accordance with the present invention by providing a tumbler lock and key assembly comprising a lock housing and a back and forward movable lock bolt provided with a lock pin or the like, and a tumbler disc assembly movable with a key and provided with a locking channel arranged to cooperate with said locking pin for controlling the displaceable movements of the lock bolt and comprising at least a first branch and a second branch disposed transversely with respect to the displaceable movement of the lock bolt, and a third branch connecting them, the tooth The keys for each tumbler disc comprise a combination surface which, when the key is turned in the lock, moves the tumbler disc in the direction of said first branch and the second branch to select a locking combination.

In particular, the present invention provides that the key tooth comprises a guide member which affects the latch of the lock such that, at the final stage of the selective tumbler disc movement, the lock pin simultaneously guides the said lock channel into said third leg of the locking channel, a guide means which is configured to prevent movement of the locking pin

by said third branch if the key combination surface is incorrect.

Said third branch of the locking channel may advantageously comprise a guide surface inclined with respect to the displaceable movement of the lock bolt and arranged to cooperate with the locking pin.

Said third branch of the locking channel may also advantageously comprise a projection defining a channel which is arranged on the opposite side of said inclined guide surface of the third branch and which together with said guide surface acts on the locking pin and guides it in the direction of selective movement of the tumbler disc.

The shape and / or size of said guiding means of said third branch in the locking channel of the tumbler disc may advantageously be arranged to be variable, wherein the corresponding shape of the key combination surface may be arranged such that it may change correspondingly so that the combination surface o a certain shape ensures functional compatibility of the locking pin only with a locking branch provided with guiding means having a certain shape and / or size.

The locking channel may, in a known manner, comprise a fourth branch which is transverse to the displaceable movement of the lock bolt and a fifth branch which connects said second branch to the fourth branch, said fifth branch also comprising said guide means for guiding the locking pin.

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The cross-section of the locking pin in the direction of selective movement of the tumbler disc is preferably triangular.

The present invention also relates to a key blank for the aforementioned tumbler lock and key assembly. The tooth of the key blank may advantageously be provided with a guide member that extends outwardly from the level of the tooth and which is arranged to move the lock bolt and hence the locking pin before the selective movement of the lock tumbler disc is completed.

On the other side of the tooth of the key blank, there may be another guide member that is located symmetrically with respect to said first guide member.

The key blank may further comprise two toothed portions that are symmetrically disposed on both sides of the mandrel blank.

The present invention further provides a key milled from the above blank. The key tooth may advantageously be provided with a guide member extending outwardly from the level of the tooth and configured to move the lock bolt and hence the locking pin before the selective movement of the tumbler discs is completed, the combination surfaces providing said selective tumbler movement. the disks are arranged on the key tooth on both sides of said guide member in the direction of the key mandrel.

The key tooth may advantageously comprise a guide surface, independently of said guide member, for providing sliding movements of the lock bolt after the selective locking movement.

a combination, wherein said guide surface and said guide member are arranged at the same cross-sectional level with respect to the key mandrel.

Alternatively, at least two different types of combination surfaces whose shapes are different from each other and which are arranged to be functionally incompatible with the tumbler disk according to another respective alternative may be selected as the combination surface for the individual tumbler disc. to contain either one of said types of combination surfaces or any combination thereof.

Said types of combination surfaces include planar surface milling and milled surfaces comprising two oppositely directed bevels facing a portion of the tooth tip.

The key tooth may advantageously comprise at least such a combination surface comprising a tip formed by oppositely angled slopes in a perpendicular cross-sectional plane of the key mandrel.

The key may further preferably comprise two toothed portions provided with combination surfaces and located symmetrically on both sides of the key blank, wherein the combination surfaces of the toothed portions are at least partially different from each other either in terms of milling value or in terms of type of combination surface.

In accordance with the present invention, a key tooth is provided with a guide member which acts on the latch of the lock such that, in the final stage of the selective movement of the tumbler disc, Simultaneously, the locking pin leads into said third branch of the locking channel. In addition, said third branch of the locking channel comprises at least one guide means for guiding the locking pin simultaneously with the displaceable movement of the lock bolt and the selective movement of the tumbler disc.

Since, in accordance with the present invention, the movement of the locking pin into a branch connecting the locking branches of the locking channel, and in this branch at least in the initial phase of the locking pin movement requires simultaneous movement of the tumbler disc, this case does not work.

By means of the solution according to the invention, it is also possible to create keys of corresponding old locking systems functionally incompatible, since these keys require a first selective movement of the tumbler discs and only then a translational movement of the lock bolt and its locking pin. Therefore, it is possible to take advantage of completely new key combination alternatives.

In practice, said third branch of the locking channel preferably comprises a guide surface inclined with respect to the displaceable movement of the lock bolt and arranged to cooperate with the locking pin.

In addition, said third branch of the locking channel may comprise a projection defining a channel which is arranged on the opposite side of said inclined guide surface of the third branch and which together with said guide surface acts on the locking pin and guides it in the direction of selective movement of the tumbler disc. Although it is thus possible to move the locking pin to the respective third branch of the locking channels on all tumbler discs, the protrusion prevents the locking pin from moving forwardly in the respective branch unless all tumbler discs are also correctly moved at the same time.

The different key combinations may advantageously be achieved such that the shape and / or size of said guide means of said third branch in the locking channel of the tumbler disc are arranged to be variable. In this case, the corresponding shape of the key combination surface can then be varied accordingly such that the combination surface of a particular shape ensures the functional compatibility of the locking pin only with the locking branch provided with guiding means having a certain shape and / or size.

The locking channel may, in a known manner, comprise a fourth branch which lies transverse to the displaceable movement of the lock bolt and a fifth branch which connects said second branch and the fourth branch. In this case, the fifth branch of the guiding means is consequently required in order to open the lock, two successive selective movements due to the key must be carried out, which increases the number of alternative combinations, while also improving the possibility of preventing the lock from opening. pin.

key.

In practice, it is advantageous to achieve a locking pin which is compatible with said limiting members and guide surfaces if the cross-section of the locking pin is triangular in the direction of selective movement of the tumbler disc.

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The tooth of the key blank of the present invention is provided with a guide member extending outwardly from the level of the tooth and configured to move the bolt of the lock and hence the locking pin before the selective movement of the tumbler discs of the lock is complete. On the other side of the tooth of the key blank is preferably another guide member which is arranged symmetrically with respect to said first guide member.

The key blank may further comprise two toothed portions that are symmetrically disposed on both sides of the mandrel blank.

The key tooth of the present invention has a correspondingly guiding member that extends outwardly from the level of the tooth and which is configured to move the bolt of the lock and hence the locking pin before the selective movement of the tumbler discs of the lock is complete. The combination surfaces providing said selective movement of the tumbler discs are disposed on the key tooth on both sides of said guide member in the direction of the key mandrel. In this case, there is an equal number of combination surfaces on both sides of the guide member, so that the key can be used advantageously from both sides of the lock.

The tooth (8b) of the key (8) also comprises a guide surface (8e), independent of said guide member, for providing sliding movements of the lock bolt (3) after the selective movement of the locking combination. Said guide surface (8e) and said guide member (8d) are arranged at the same cross-sectional level with respect to the mandrel (8a) of the key (8).

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The number of locking combinations available can be substantially increased if at least two different types of combination surfaces can alternatively be selected as the combination surface for a single tumbler disc. These combination surface alternatives may be arranged to be functionally incompatible with the tumbler disc according to another relevant alternative, since compatibility with the tumbler disc only requires that certain changes required for each type of combination surface be made in the tumbler disc locking channel. The combination surfaces of the key may then be selected to include either one of said types of combination surfaces or any combination thereof.

Said types of combination surfaces may advantageously comprise planar surface milling and milled surfaces comprising two oppositely directed bevels facing a portion of the tooth tip. In practice, the key tooth preferably comprises at least one such combination surface which comprises a tip formed by opposing slopes in a perpendicular cross-sectional plane of the key mandrel. The mixed use of different types of combinations makes it difficult to remember the combination values of the key and thus the possibility of unauthorized production of the key.

The number of combination alternatives can be further multiplied if the key comprises two toothed portions provided with combination surfaces and located symmetrically on both sides of the key blank. In this case, the combination surfaces of the toothed parts may be at least partially different from each other, either in terms of the milling value or in terms of the type of the combination surface.

PO11

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail below with reference to the accompanying drawings, in which:

Figures 1 to 6 show views of the lock according to the invention in its various operating positions, viewed from the side and with the lock housing lid removed;

Fig. 7a is an enlarged view of the tumbler disc of the lock with its locking channels;

Fig. 7b shows schematically the movement of the locking pin in the locking channel of the tumbler disc of Fig. 7, in different operating positions of the lock;

Fig. 8 shows various combinations of lock key milling alternatives; and Fig. 9 is a cross-sectional view taken along the line IX-IX in Fig. 8.

DETAILED DESCRIPTION OF THE INVENTION

In the drawings, the reference numeral 1 denotes a lock housing intended to be installed in a door leaf or the like, including a front plate 2 and a lock bolt 3 movable back and forth between a protruding locked position and a retracted unlocked position by means of a key 8. of the castle. For this purpose, the lock housing 1 is preferably provided with a keyhole 1b on both sides. The key 8 is provided with a mandrel 8a which is further provided with a mandrel 8a. provided with two toothed portions 8b1 and 8b2.

The lock housing 1 is provided with a set of tumbler discs 5 which are separated from each other by spacers 7 ^and which form a branched locking channel for the locking pin in the lock bolt 3. In order to control the movement of the locking pin and thus of the lock bolt 3, the lock is provided with a guide groove 1a.

7a, the locking channel in the illustrated embodiment comprises locking branches 5a, 5b and 5d, as well as branches 5c and 5e interconnecting them. If the locking pin 6 moves through the branches 5c or 5e, then the lock bolt 3 moves simultaneously from one position to another. The branch 5c is provided with an inclined guide surface 5f and a guide projection 5g, correspondingly the branch 5e is provided with an inclined guide surface 5i and a guide projection 5h which serve to guide the movement of the locking pin 4 as shown in FIG. 7b.

In practice, because of the guide groove 1a, the movement of the lock bolt 3 and the locking pin 4 is linear, so that displacement of the lock bolt 3 requires corresponding movements of the tumbler discs 5. The locking channel may also be provided with a recess 5j which together with the recess 4a of the locking pin 4. It makes it difficult to detect the position of the tumbler discs 5 and thus also to open the lock by means of the key.

8 and 9, the key 8 is provided with combination surfaces 8c (8c1, 8c2, etc.) for each tumbler disc 5;

correspondingly, the tumbler discs 5 are provided with stop surfaces 5k for the combination surfaces 8c of the key 8. If the key 8 is rotated in the lock to select the locking combination, the tumbler discs 5 move upwards in the figures of Figures 1 to 6. and are guided by pins 9a and 9b of the lock housing 1 against the force of the spring 6.

The combination surfaces are milled on the tooth of the key 8 of the lock. In the present embodiment, the key 38 is provided with two toothed portions 8b1 and 8b2. These toothed portions 8b1 and 8b2 together with the three locking branches 5a, 5b and 5d form two protruding positions of different length for the latch bolt 3, which can be achieved by two successive movements of the tumbler discs 5 caused by the key 8.

Referring to FIG. 1, FIGS. 2 and 9, the toothed portions 8b1 and 8b2 of the key 8 are further provided with guide members 8d (8d1, etc.) acting on the guide surfaces 3a1, 3a2, 3b1 and 3b2 of the bolt 3. lock in order to displace this lock bolt 3 in the final stage of each selected movement of tumbler discs 5 such that the locking pin 4 is guided into the lock channel branch 5c or correspondingly into the branch 5e. Furthermore, the toothed portions 8b1 and 8b2 of the key 8 are provided with guide surfaces 8e1 and 8e2 in order to achieve actual displaceable movements of the lock bolt 3 after the selected movement of the locking combination. For this purpose, the latch bolt 3 is provided with guide surfaces 3a3 and 3b3.

The function of the lock is as follows:

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Μ. ’.. · · .. ·

In the initial position according to FIG. 1, the latch bolt 3 lies in an outwardly protruding position, the locking pin 4 being in the locking branch 5a of the tumbler disc locking channel 5. If the key 8 is rotated, the combination surface 8cl abuts the stop counter surface 5k. As a result, tumbler discs 5 move upward in the figures against the force of the spring 6. At the same time, the proportional position of the locking pin 4 in the locking branch 5a changes.

Then, in the final stage of the selected movement of tumbler discs 5, the guide protrusion 8d12 on the key 8 engages the guide surface 3a1 of the latch bolt 3 and begins to move the latch bolt 3 to the right in Fig. 2 as the tumbler discs 5 move as they are moved. By means of the combination surfaces on the key 8. As a result of the combination of these movements, the locking pin -4 is first guided into the locking channel branch 5c and then further forward until the movement of the tumbler discs 5 is complete, provided that analogous combination surfaces the keys are correct.

Then, in the situation of FIG. 3, the guide surface 8el of the key 8 acts on the stop surface 3a3 of the lock bolt 3 and moves the lock bolt 3 forward, while at the same time the locking pin 4 moves in the branch 5c below the guide projection 5g. However, the displacement of the locking pin 4 over the branch 5c is only successful with the correct combination of the above movements. For example, if the selected movement of the tumbler discs 5 has already been completed, the guide protrusion 5g can prevent movement of the locking pin 4 in the branch 5c of the locking channel. In a similar manner, the guide surface 5f prevents movement of the locking pin 4 in the branch 5c.

If the corresponding combination surface of the tumbler discs 5 is incorrect in terms of the combination value or type-type of the locking channel. combination surfaces.

In the situation of FIG. 4, the locking pin 6 has already been moved to the position of the locking branch 5b of the locking channel. In this case, the tumbler discs 5 move downwards in FIG. 4, being pressed by the force of the spring 5, while at the same time their guide surfaces 5k and the combination surfaces 8cl remain in contact with each other. At this stage, the guide member 8d11 on the other side of the toothed portion 8b1 of the key 8 acts on the guide surface 3a2 of the lock bolt 3 and the guide surface 8e1 of the key 8 correspondingly acts on the guide surface 3a1 of the lock bolt 3 in the locking branch 5b of the locking channel. As a result, when further turning the key 8, the locking pin 4 is able to move to the end of the locking branch 5, as can be seen from FIG. 5.

The movement of the lock bolt 3 and the locking pin 4 from the position of FIG. 5 to the position according to FIG. 6, when the lock bolt 3 is fully retracted and the key 8 is removed from the lock, occurs in a completely analogous manner to that described above. by turning the key 8 further in the same direction. If the latch bolt 3 is moved back to its protruding position, the above operations are carried out accordingly, but in reverse order.

7a and 7b, the guide surfaces 5f and 5i of the locking channel and, on the other hand, the guide protrusions 5g and 5h can be seen. • Somewhat different from each other. • • • • • • • • • • Correspondingly, the combination values of the combination surfaces 8c121 and 8c232 of the opposite toothed parts of the key 8 in Figures 1 to 5, but in particular the shapes of these surfaces, differ from one another (see Figure 9).

In this way, two different shapes of the combination surfaces can be used as the combination surfaces of the key for each combination value whose compatibility with the locking channel of the tumbler disc is precisely determined by the shape and location of the abovementioned guide surfaces and guide projections. such that the respective shape of the combination surface is only compatible with a certain type of shape of the guide surface and the guide projection. This is based on the fact that the types of combination surfaces described, which differ from each other, provide movements that differ somewhat from each other in the final stage. Alternatives to the different combination surfaces are shown schematically in Fig. 8 and Fig. 9.

Although in the present embodiment, two different tumbler disc choices are provided by two toothed key portions 8b1 and 8b2, one for each protruding length of the lock bolt 3, a very large number of different locking combinations can be achieved.

For example, provided that it is a symmetrical lock into which a key can be inserted from both sides thereof, the key being provided with two toothed portions facing each other and provided with combination surfaces for eight tumbler discs, four different combination combinations can be achieved. values for each combination surface, wherein parts thereof may be provided with two different theoretically combination surfaces, to achieve a number of 16777216 different locking combinations. Of these, at least 1005480 combinations may be used in practice. In the case of a asymmetric lock, a significantly higher number of combinations can be achieved accordingly.

shapes possible

It is to be understood that the present invention is not limited to the embodiments shown, as many modifications are possible within the scope of the following claims.

Claims (15)

PATENT CLAIMS A tumbler lock and key assembly, comprising a lock housing (1) and a lock (3), a back and forward movable lock bolt (3) provided with a lock pin (4) or the like, and a set of tumbler discs (5) movable by means of a key (8) and provided with a locking channel which is arranged to cooperate with said locking pin (4) for controlling the displaceable movements of the lock bolt (3) and comprising at least a first branch (5a) and a second branch (5b), and a third branch (5c) connecting them, the tooth (8b) of the key (8) comprising, for each tumbler disc (5), a combination surface (8c) which, when turned by the key (8) in the lock moves the tumbler disc (5) in the direction of said first branch (5a) and second branch (5b) for selecting a locking combination, characterized in that the tooth (8b) of the key (8) comprises a guide a member (8d) that affects the lock bolt (3) such that, at the final stage of selective movement of the tumbler disc (5), the lock pin (4) simultaneously leads to said third branch (5c) of the locking channel, said third branch (5c) The channel comprises at least one guide means (5f, 5g) which is arranged to prevent movement of the locking pin (4) by said third branch (5c) if the combination surface of the key (8) is incorrect. Assembly according to claim 1, characterized in that said third channel (5c) of the locking channel comprises a guide surface (5f) inclined relative to the displaceable movement of the lock bolt (3) and arranged to cooperate with the locking pin (4). • • • • Assembly according to claim 2, characterized in that said third branch (5c) of the locking channel comprises a projection (5g) defining a channel which is arranged on the opposite side of said inclined guide surface (5f) of the third branch (5c) and which together with said guide surface (5f) acting on the locking pin (4) and guiding it in the direction of selective movement of the tumbler disc (5). Assembly according to any one of the preceding claims, characterized in that the shape and / or the size of said guide means (5f, 5g) of said third branch (5c) in the locking channel of the tumbler disc (5) are arranged to be variable, the shape of the combination surface (8c) of the key (8) is arranged such that it can be varied accordingly such that the combination surface (8c) of a certain shape ensures functional compatibility of the locking pin (4) only with the locking branch (5c) provided with guiding means (5f, 5g, 5h, 5i) having a certain shape and / or size. Assembly according to any one of the preceding claims, characterized in that the locking channel comprises in a known manner a fourth branch (5d) which lies transversely to the displaceable movement of the lock bolt (3) and a fifth branch (5e) which connects said second branch (5b). ) and a fourth branch (5d), said fifth branch (5e) also comprising said guide means (5h, 5i) for guiding the locking pin (4). An assembly according to any one of the preceding claims, wherein the cross-section of the locking pin (4) in the direction of selective movement of the tumbler disc (5) is triangular. A key blank for an assembly according to any one of the preceding claims, characterized in that the tooth (8b) of the key blank is provided with a guide member (8d) extending outwardly from the level of the tooth and configured to move the bolt (8b). 3) the lock and hence the locking pin (4) before the selective movement of the tumbler disc (5) is completed. A key blank according to claim 7, characterized in that on the other side of the tooth (8b) of the key blank there is another guide member (8d) which is arranged symmetrically with respect to said first guide member (8d). A key blank according to claim 7 or characterized in that it comprises toothed portions (8b1, 8b2) that are located symmetrically on both sides of the key blank. two on A key milled from a blank according to any one of claims 7 to 9, for use in an assembly according to any one of claims 1 to 6, characterized in that the tooth (8b) of the key (8) is provided with a guide member (8d) extending outwardly from the tooth level, and which is arranged to move the lock bolt (3) and hence the locking pin (4) before the selective movement of the lock tumbler discs (5) is completed, the combination surfaces (8c) providing said selective tumbler disc movement (5) are arranged on the tooth (8b) of the key (8) on both • 00 - sides of said guide member (8d) in the direction of the mandrel (8a) of the key (8). A key according to claim 10, characterized in that the tooth (8b) of the key (8) comprises a guide surface (8e), independently of said guide member (8d), to provide sliding movements of the lock bolt (3) after selective movement of the locking combination; said guide surface (8e) and said guide member (8d) being arranged at the same cross-sectional level with respect to the mandrel (8a) of the key (8). Key according to claim 10 or 11, characterized in that at least two different types of combination surfaces whose shapes differ from one another and which are arranged so as to be alternatively selected as the combination surface (8c) for the individual tumbler disc (5), to be functionally incompatible with the tumbler disc (5) according to another respective alternative, wherein the combination surfaces (8c) of the key are selected to include either one of said types of combination surfaces or any combination thereof. The key of claim 12, wherein said types of combination surfaces include planar surface milling (8cl11, etc.) and milled surfaces (8cl12, etc.) comprising two oppositely directed bevels facing the tooth tip portion. A wrench according to claim 12 or 13, characterized in that the tooth (8b) of the wrench (8) comprises at least a combination surface (8c) which: · Comprises a tip (8cl12) formed by opposing slopes in a perpendicular cross-sectional plane of the key (8a) of the key (8). Key according to any one of the preceding claims 10 to 14, characterized in that it comprises two toothed parts (8b1, 8b2) provided with combination surfaces and located symmetrically on both sides of the key blank (8a), the combination surfaces (8c1, 8c2). the toothed portions (8b1, 8b2) are at least partially different from each other, either in terms of the milling value or in terms of the combination surface type.