Presently numerous versions of Chubb system safety locks, that is locks operated with keys with one or two key-bits, are known. Among these, in respect of the number of variations only those meet the safety requirements which extend in the direction of the axis of the key (considering a key put in the lock), that is their plate is thick, and they are rather extended in the other two directions, too. The disadvantages resulting from this are well-known (more material, more cost, a bigger indented hole in the door in the case of indention, which weakens the door, etc.) The task to be solved with the invention is to make a small, safe and otherwise high-strength lock with a high number of varieties, and an improved locking system needed for it. According to current technology, in the case of lever locks, which need to be made so that they can be operated from both sides (as it is generally done in the case of building doors), the number of variations is usually especially low as compared to locks operated from one side, e. g.: safe locks. While in the case of locks used from one side, the part-the tooth width-which is connected to the bolt and is needed to move the bolt, is to be reduced from the complete width of the key-bit, in the case of keys used from both sides the same tooth width is to be reduced twice because of the symmetry, and only the remaining part can be cut with teeth allocated to the levers. It is especially so in the case of locks, e. g.: in the case of Elzett No. 700, where the stem of the bolt is not placed in the middle of the striking plate, but somewhere else. In the case of bolts situated in the middle of the striking plate, only half of the width of the tooth moving the bolt is to be reduced from the half-width f the key-bit. However, in the case of indented locks this possibility is generally not used, because the number of levers is normally increased by doubling them as a result of the symmetric position of the individual levers, and by this the number of variations is not increased, but it results in some extra protection against Hobbs type opening. In the case of screw-on locks, where the width of the plate is not so restricted, the on the one side of the bolt stem situated in the middle an appropriate number of levers need to be placed, and due to this the width of the key-bit also increases.

Due to the above the task to be solved with the invention is to create a lever lock which can be operated from two sides, the stem of the bolt is not in the middle, and at the same time the tooth-width needed for the bolt is not reduced from the width of the key-bit, so the part remaining in this way can also be provided with one or two further levers which increase the exponent producing the number of variations.

Another task to be solved with the invention is to make the levers in a way that a small locking system, in respect of the width and height of the striking plate, and by this small locks can be made.

More generally the invention relates to a locking system of increased safety, which has a striking plate created by a bottom plate, cover plate and front plate, or similar to it, in which- according to any of the already known ways-there is a bolt, making linear motion possible, protruding from the striking plate, connected to the levers in co-operation with it, made in a way that it determines the closed and open positions of the bolt, and on the striking plate there are keyholes made for a turnable key in co-operation with the bolt, realising rotating cyclic mechanism with the levers, and in the striking plate there is a disc provided with at least one tooth, embedded in a way allowing concentric rotation with the keyhole, suitable for taking the key.

Furthermore, the stem of the keys (whether they have one or two key-bits) used for the known locks is cylindrical, and for this reason they are expensive to produce, because the key stem cross section which is thicker than the key-bit or the key-head can only be made by casting or by difficult compression. By making a cylindrical tongue made axially on the central part of the disc embedded in the lock in a rotating way, and by practically embedding this tongue, it also becomes possible to make a flat key the stem width of which is more or less the same as the width of the key-bit or key-head.

Below the invention is demonstrated with drawings, where Figure 1 shows a lock according to the invention, with its cover plate taken off, at a scale of 1: 1, in the basic open position of the lock, Figure 2 shows the lock as in drawing 1, in the A-B section shown there, Figure 3 shows the lock according to drawing 1, with the key inserted, in section, in the position after the first quarter turning of the key in the course of the locking process, and in the position after the last quarter turning of the key in the course of the opening process, Figure 4 shows the lock according to drawing 3 in the same position, in section C-D shown there, Figure 5 shows the disc shown in the previous drawings, axonometricly, at a scale of 1: 1, while Figure 6 shows a part of the key, also axonometricly, positioned axially against it, Figure 7 shows a part of the lock in a position according to the A-B section (drawing 2), with a key inserted into it, turned into a position according to section C-D (drawing 4), at a scale of 2: 1, Figure 8 shows another lock made with a lever system different from the one shown in drawings 1-4, in the same way as in drawing 1, Figure 9 shows section E-F shown in drawing 8, Figure 10 shows the lever according to another favourable construction shown in drawings 8 and 9, in a position as in drawing 8, Figure 11 shows a further favourable arrangement of the disc and the bolt in a position according to section E-F as in drawing 9, Figure 12 shows the bolt and the disc together, belonging to the newer lever system shown in drawing 8, the rest of the components have been removed, in a position of the disc, or the key that is not shown here, after one-eighth of a turn, Figure 13 also shows a disc, but unlike the above solutions, in a construction suitable for a key with one key-bit, in an axonometric view, at a scale of 1: 1 used above, Figure 14 shows a disc in axonometric view, at a scale of 2: 1, which has the same central cylindrical tongue as the one in drawing 13, but it is for a flat and not a cylindrical key, which has two key-bits in this case again, Figure 15 shows a flat-stem key in the same view as in drawing 14, in the same axial position, and finally Figure 16 shows the disc as in drawing 14, in a position according to drawing 2, at a scale of 1: 1.

Obviously the individual parts of the favourable constructions of the invention shown in the drawings can be combined with each other for the purpose of creating further favourable constructions, and they can also be combined with the parts of other locks already known. As a result of this not only bolt locks shown in the drawings, but also catch locks, handle locks, switch locks, mortise locks and screw-on locks can also be made.

Starting the detailed description of the invention with drawing 1, there is a lock 1 in basic position, its plate consists of a bottom plate la and a cover plate lb, and the latter one can be seen first in drawing 2. In the front the striking plate is closed with a front plate 2 characteristic of mortise locks, and the bolt-head 3 a of a bolt 3 is put through its opening. The bolt 3 has got a disc-like bolt stem 3b inside the lock 1, as usual. The lock 1 itself is made so that its overall dimensions are not bigger than those of the lock known in Hungary as Elzett 700, but rather it is less wide, which is made possible by its different internal structure. This construction, just like any of the other constructions shown in the drawings, is suitable for use in other locks, too, or for making locks constructed like other type of locks, with the same insertion dimensions.

Continuing the description with the locking system of the construction according to drawing 1, there is a cylindrical bolt pin 3c which is attached to the bolt stem 3b, and onto which levers 4 are placed which can turn to a restricted extent. A further advantage is that the bolt pin 3c is beside the bolt head 3a, although it could also be at the other end of the bolt stem 3b, but this is how it is possible to reduce the width of the lock 1 even in the case of using turning levers 4.

Obviously the solution contains more levers 4, but only one can be seen in drawing 1, as it is enough to understand how it works. The lever 4, constructed as described above, has a window 4a made to co-operate with the key and the gate pin Id. The gate pin Id, which is favourable fixed into the bottom plate la, is also for driving the bolt 3 straight, so in this case there is also a slot 3d in the bolt stem 3b. The lever 4 is continuously held against the gate pin 1 d with a spring 4b made in the normal way, attached to the bolt 3, supported against the pin 3e, fixed into the lever 4 at the bottom, or, in the given case it is held against the key-bit in a position stopped from above.

It follows from this that the gate pin I d can be fixed onto the bolt stem 3b, and the bolt pin 3c can be fixed onto the bottom plate la by rearranging the window 4a in an appropriate way, and inside this the bolt pin 3c could also be somewhere close to the bolt head 3a or somewhere close to the end of the lock 1. On the basis of already known locks the description of the exact place and shape of the mentioned parts does not need to be explained in detail to specialists.

The possible ways of fixing together the bottom plate la to the cover plate I b do not need to be explained either, one of the possible solutions is to use a screw-house Ic as shown in drawing 1.

The above description of the invention, including the details that can be seen in drawings 2, 3 and 4, offer a favourable further development of presently known locks. Furthermore, another significant advantage is that according to drawings 2 and 4 the bolt 3 has a thickened bolt stem 3b, made from two plates in this case, and due to this the strength of the bolt 3 completely drawn out from the lock 1 is significantly greater with respect to bending use.

Another advantage of the invention is that a disc 5 is embedded in the lock 1 in a turnable way. On the lock 1, in the case of the present construction, a keyhole If is made for the key in the usual way, and for this a connecting hole 5a, the size of which suits the key-bit, is made on the disc 5. As the disc 5 is placed axially with respect to the keyhole If, the key inserted into the lock 1 can be turned around. A new development in the case of this solution is the use of the disc 5, because in this way the number of levers on it can be increased, and it has a role in increasing the combinations and the number of variations that can be achieved in the lock 1.

According to the traditional way on the key-bit-considering a lock that can be operated from two sides-the connection between the key and the bolt 3 should be created at least on one place-if the bolt stem 3b is in the middle of the striking plate, on its dividing line-so that this connection results in the progressing movement of the bolt 3 when the key is turned. This is a possible arrangement of the bolt stem 3b, but not the best one, because on the one side of the bolt stem 3b less than half of the inside dimension of the levers 4 perpendicular to the bolt stem 3b inside the striking plate remains, which can be dissatisfactory especially in the case of mortise locks. But if the bolt stem 3b is not in the central place, then the construction made on the key-bit in the interest of making a connection with the bolt stem 3b to make operation possible from both sides, is asserted twice due to the width of the bolt stem 3b.

Only the levers on the one half of the plate of the lock 1, including the one placed in the middle, increase the number of variations as the ones determining the number of the exponent.

This characterises all traditional lever mortise locks. An efficient way of increasing the number of variations is cutting the key-bit exclusively for levers. Due to the present solution it can be achieved by using a disc 5, as on the disc there is a tooth 5b, or there are teeth, made in the interest of creating connection with the bolt stem 3b always on the same place, and due to this the function of the key-bit is taken over in this respect.

The described construction also includes a key 6, which can be seen in drawings 3,4,6 and 7, to show how it fits into the disc 5, and to show that the key-bit 6a of the key 6, or in this case its key-bits 6a, are not equipped with parts serving the purpose of direct connection to the bolt stem 3b, and for this reason the complete width of the key-bit 6a is constructed to make connections with the levers 4.

It is best shown in drawing 7 that the key-bit 6a protruding into the connecting hole 5a, independently from its actual radial extension on the given part-suiting the given levers 4, obviously in the case inserting the key from the other side of the lock 1 as compared to what is shown in the drawing-, can turn the disc 5, at the same time the tooth 5b replaces a key-bit of permanent extension, having a permanent radial dimension on this place.

In drawings 1-7, on the basis of the given signs in the drawing the operation and several advantages of the invention can be studied without explaining the drawings individually. In the interest of better understanding, in drawings 3 and 4 the levers, or their group, are only shown with dots and dashes. However, the method of embedding the disc 5 is not shown, but it is unnecessary, as the method can be studied on many ring locks in the lock industry. In the case of the shown construction, where the aim was also to show a solution to be followed in the case of locks made in smaller sizes, it can be see that place can be ensured with a small window (drawings 2 and 7) cut into the folded up edge of the bottom plate la on the one part, and on the other part lateral support can also be ensured by it. Of course there are free options also in respect of the other details, for example the construction of the bolt 3, according to the known technologies. The shown bolt stem 3b built from two plate layers, is not the only possibility.

The connection between the disc 5 and the bolt 3 or its bolt stem 3b in the course of turning is not explained, and the exact construction of the bolt stem 3b does not need to be explained either to specialists. This is why the levers 4 are not shown in drawing 7.

As compared to the traditional locks another advantage is that in order to attach the key addresses there are openings Ig in the bottom plate la and the cover plate lb for the screws going through the striking plate, preferably with spacing according to some standard, e. g.: DIN standard.

Drawings 8-10 show another favourable construction which does not have the same variation possibilities as in the case of the turning levers 4 used in the previous drawings, i. e. that the levers 4 can be constructed in a way that they turn around a point fixed to the bottom plate la or the bolt stem 3b, that is around the bolt pint 3c. In the case of the small lock 1 chosen to introduce the construction, according to drawings 8-10, the levers 4 are driven along a straight vertical line in relation to the bottom plate la. In the case of a bigger lock, on a bigger bolt stem 3b, in a favourable case the levers 4 can also be constructed in a way that they are driven along a straight vertical line with the help of channels made on the bolt stem 3b, on the basis of already known methods. The moving of the levers 4 driven along the bolt stem, both with turning levers and levers driven straight, will be complex in relation to the bottom plate la.

In drawings 8-10 and in drawing 12 the moving of the levers 4 is simple as a result of adjusting to the small lock dimensions, for the sake of the example it is demonstrated in the given small lock 1. Here the levers 4 are driven between two extensions which are the folded down extensions of the lower pin I h fixed in the bottom plate la and the upper bridle li. In the case of this construction it is necessary to ensure the driving of the bolt 3 with an ear 3f folded out from the lower layer at its upper right corner, between the horizontal part of the bridle li and a horizontal slot laa of the bottom plate la as a horizontal channel. The extensions of the vertical parts of the li bridle, between which the levers 4 are placed held by their upper part, can fit into the openings of the cover plate lb made for this purpose, and the extension lia made to support the upper end of the strings 4b can also fit into them.

In the drawings mentioned above the other details and the disc 5 operate in the same way as described before. The special construction due to the small dimensions is worth mentioning in connection with the present construction of the lever 4 which has two feet 4c. The two feet 4c encase the keyhole If, and they ensure the more precise driving of the levers 4. Vertical, ascending and descending, levers 4 are more favourable, because in this case the internal construction of the window 4a makes smaller steps possible, that is more variations inside the levers, and as a protection against the Hobbs type opening it also makes the so-called, wolf s teeth"construction possible, as it operates more precisely than a turning lever.

In drawing 10 the spring 4b is shown only with dots and dashes in relaxed position. In this way a slot 4b usually made to fix the spring 4b can also be seen.

The purpose of drawing 11 is to show that in connection with the construction of the bolt stem 3b, the disc 5 can be placed not only beside the bottom plate la, unlike in the previous cases, so the teeth 5b can even point towards the bottom plate la.

The purpose of drawing 13 is to show that on the one part the disc 5 with one tooth 5b can also be used in locks where the key has one key-bit, and on the other part it shows that the central part of the disc 5 can also be made with a cylindrical extension 5c. On the one part the cylindrical extension 5c provides the disc 5 with a further possibility of embedding, as it can be made so that it protrudes into the cover plate 1 b, the central part of the keyhole If extended for this purpose, on the other part with a channel 5d it is made in a shape and in a size suiting the stem 6b of the key 6, which has a circular section in this example. The disc with an extension 5c can be easily produced from a zinc casting or using powder metallurgy, unlike the disc shown in drawings 1-12, which can also be produced easily from a steel plate, by compression.

In the case of the disc 5 shown in drawing 13 it can be seen that the most important part of the tooth 5b is the protrusion at the outer end of the connecting hole 5a, but it does not exclude the construction surrounding the connection hole as in drawing 5.

In the case of the construction shown in drawings 14ü16 the stem 6b of the key 6 is not cylindrical, but flat, and the connecting hole 5a of the disc 5 and the channel 5d in the extension 5c is made to suit it. Obviously the extension 5c does not necessarily have to be there, because the key 6 can also be turned around in the widened out version of the central part of the keyhole If made in the bottom plate la and the cover plate lb, suiting this flat version of the stem 6b, but it is favourable to have it. According to the construction described here keys can be easily produced from a 2-3 mm thick plate, e. g.: from steel or brass. The disc 5 occurs as an extra cost only once per lock, but it is counterbalanced by what you save when you have several keys. Of course the key 6 made with a flat stem 6b can also be used with a disc 5 which does not have a tooth 5b, mainly in the case of traditional locks.

In respect of the details the favourable constructions of the invention can be combined with each other and with the solutions used in already known locks.

In drawing 13 and 15 the disc 5 can also be made so that it is driven by only the two ends of the extension 5c, without its circular dimension, only with the part left around the connecting hole 5a. Any version of the disc 5 can be positioned in its basic position in a known way, e. g.: with an arresting device.

List of references 1 lock 1 a bottom plate laa horizontal slot lb cover plate 1 c screw-house 1 d gate pin le screw-house If keyhole I g opening I h lower pin li upper bridle lia extension 2 front plate 3 bolt 3 a bolt-head 3b bolt stem 3c bolt pin 3d slot 3e pin 3fear 4 lever 4a window 4b spring 4c foot 5 disc 5a connecting hole 5b tooth 5c cylindrical extension 5d channel 6 key 6a key-bit 6b stem