EP0261298B1 - Flat key profile for a cylinder lock key - Google Patents

Description

The invention relates to a flat key for cylinder locks, which has longitudinal grooves on both flat sides, which, starting from a key blank divided into lines, the line height being given by the opening side of the longitudinal groove, being arranged in the lines, with each line either at one or a longitudinal groove is arranged on the other flat side or a longitudinal groove is arranged on both flat sides.

The invention also relates to the corresponding cylinder lock.

A flat key of the type described above is known from AT-B-371 879.

For the commercial production of flat keys for cylinder locks, it is necessary to profile the key flat sides according to a certain system. With different keys it is often desirable that they also have different profiles so that they cannot be inserted into other cylinder locks of the same profile system.

On the other hand, for cost reasons, there is a need to make the mechanical changeover for generating different key profiles as simple and inexpensive as possible. As little as possible different profile elements should be used.

The object of the present invention is to meet the above-mentioned requirements and to provide a profile arrangement which permits the production of individual keys, that is to say one-of-a-kind, thus of keys which have no hierarchical relationship with one another. In the case of such unique items, it is not possible to convert one profile into another profile of the same profile system by post-processing.

According to the present invention, the flat key is characterized in that all grooves are designed according to one of three profile types and all grooves of one profile type have the same cross-sectional shape and the same profile depth, with the arrangement of the longitudinal grooves arranged on one side on the flat side, the profile depth varies from the flat side to or extends over the geometric central longitudinal plane of the key blank and, in the case of the longitudinal grooves arranged on both sides on the flat sides, the profile depth is less than the distance from the flat side to the geometric central longitudinal plane, so that when longitudinal grooves are arranged on the two flat sides, these longitudinal grooves are separated by a web , and that the flat key has at least two of the profile types.

The cylinder locks according to the invention with a profiled key channel for receiving flat keys according to the invention, the key channel having ribs on both side flanks which are arranged in rows, with a rib being arranged in each row either on one or on the other flank or one rib on each flank , are characterized in that all the ribs are designed according to one of three profile types and all ribs of one profile type have the same cross-sectional shape and the same rib height, with the arrangement of the ribs arranged on one side on the flank, the rib height varying from the flank side to or above the geometric Extends the central longitudinal plane of the key channel and, when opposing ribs are arranged on both flanks, these ribs are separated from one another by a space, and that at least two of the profile types are arranged.

Further features according to the invention can be found in the dependent patent claims and the following description and the drawings.

The state of the art is explained in more detail below with reference to FIGS. 1 to 3 and the invention with reference to FIGS. 4 to 12. 1 shows the side view of a flat key with grooves on a flat side of the key. The following Figures 2 to 12 show schematic sectional views according to the section line I-I. 2 and 3 schematically show two known profile arrangements or profile systems. 4 shows the profile cross-sectional grid according to the invention and FIG. 5 shows the three basic groove types A, B and C. FIGS. 6, 7 show two different profile designs according to an embodiment of the invention. 8 and 9 schematically show the profile system for the possible groove arrangements in one line of the profile cross-sectional grid. 10, 11 and 12 show exemplary embodiments of flat keys according to the invention, the profile formation of the associated key channel being additionally drawn in FIG.

Fig. 1 shows a conventional flat key in side view. Longitudinal grooves extend in a known manner from the key chalk 1 to the key tip 2. The grooves are provided on both flat sides and are distributed over the height 3 of the key profile in accordance with the desired variation. The incisions 4 interact in a known manner with tumbler pins, not shown here, of the associated cylinder lock. The number of incisions 4 can be chosen as desired, but usually ranges between three and seven incisions.

So far, profile systems have been proposed, such as shown in FIGS. 2 and 3. The profile cross-sectional grid according to FIG. 2 sees profile elements 5 to 11 on the left key side and profile elements 12 on the right key side to 18, which can be milled from the key material depending on the desired variation. A key produced in this way, in which the profile elements 6, 9, 11, 14 and 16 have been milled out, is drawn out with a strong line in the profile cross-sectional grid.

In another known profile system according to FIG. 3, the procedure is analogous, for example by the profile elements 19, 21 and 24 are milled out.

All these known profile types or profile systems have disadvantages. On the one hand, it is relatively easy to mill another profile of the same profile system from a certain profile, which can then lock corresponding other locks. E.g. 2 subsequently removed the profile element 7, the resulting groove comprising the two profile elements 6 and 7, a fully functional new key is produced, which corresponds to the same profile system and can lock all associated locks. Even with the key drawn with a strong line in Fig. 3, e.g. by removing the profile element 22 a modified, fully functional key can be formed. Such profile changes are not a problem for suitably equipped companies, and misuse is easily possible.

Furthermore, all known profile systems of this type have the disadvantage that it is relatively simple - provided the profile system is known - to produce a superordinate key which fits practically in all locks or groups of locks according to this profile system. With the profile system Fig. 3 this happens e.g. in that the duplicate key has grooves in which all fields 19 to 24 are milled out. If such a key is made available, all profile differences serving for security will be nullified.

The invention is based on a grid of the key cross section, which is divided into several lines 25 to 29, FIG. 4. Each of these lines can be provided with one of the three profile types, which are labeled A, B and C in FIG. The longitudinal center plane of the key is designated 30 in each case.

The profile type A has a relatively deep groove 31, which starts from the left flat side of the key and protrudes beyond the longitudinal center plane 30. The right flat side remains full.

Profile type B also has a relatively deep groove 32, which extends from the right side of the key over the longitudinal center plane 30. The left flat side remains full.

Profile type C has relatively flat grooves 33 on both flat sides.

All three profile types A, B and C have grooves with dimensions such that the remaining key material is strong enough to ensure a stable key. The exact cross-sectional shape of the individual profile types is irrelevant for the basic system. The number of profile variations can be increased by choosing different profile shapes.

The profile types A, B and C can be arranged as desired over the key height within the grid Fig. 4, at least two of the profile types A, B or C being realized on a flat key.

6, 7, for example, two different profiles designed in this way are shown. 6 shows the profile sequence B-B-C-A-C and FIG. 7 shows a key with the profile sequence A-B-A-C-A. If you look at these key profiles, you can clearly see that it is not possible to rework some of the profile elements by removing key material in such a way that a profile element of a different profile type is created, which results in a lockable key. Such non-executable options are shown in broken lines in FIG. With all these possibilities, the key breaks apart along the grooves and is therefore unusable. In the first column, Fig. 6, the additional milling of a groove A would overlap with the existing groove B and the key would be cut lengthways. In the second column, milling the left part of the groove type C would result in such a small wall thickness up to the best groove B that the key breaks at this point. If the profile type C were to be modified (third column in Fig. 6), the key wall thickness would be too low and the key unusable.

8 and 9 show on an enlarged scale all possible profile elements of a preferred embodiment drawn in on a raster line. In practice, each of these types of grooves can be formed on the key only in a separate line of the cross-sectional profile of the profile.

In contrast to the embodiments shown in FIGS. 5 to 7, the grooves to be incorporated are arranged asymmetrically to the line symmetry plane 34 within each line. The embodiment in FIG. 9 is a mirror image of the embodiment in FIG. 8. The two symmetry variations can be present on a key, as can be seen in FIGS. 11 and 12.

In Fig. 8 the line consists of an upper and lower boundary line 35, 36. The left and right boundary lines correspond to the key flat sides 37, 38. Two diagonals are possible within the rectangle formed in this way, the embodiment of Fig. 8 the diagonal 39 from the left used as construction line from top to bottom right, while in the embodiment according to FIG. 9 the diagonal 40 runs from the top right to the bottom left.

In FIG. 8, the upper groove flank 41 extends in the line diagonal 39 for the groove type A. If a type B groove is to be provided, which extends from the right flat key side 38, it is the lower groove flank 42 that is in or approximately in the line diagonal 39 lies.

Both grooves A and B have a depth that extends over the longitudinal center plane 30 of the key. In cooperation with similar profile elements of other lines, a so-called. overlapped profile can be achieved, which increases the locking safety in a known manner.

The dashed lines 43, 44 are the boundary lines of the grooves according to type C in FIG. 8. As can be seen, the shape of the flat grooves of type C corresponds exactly to the shape of the grooves of type A and B, with only the depth of the groove being shortened is.

The embodiment according to FIG. 9 is self-evident on the basis of the explanation for FIG. 8. The groove types are designated A1, B1 and C1.

With regard to the above, it is emphasized again that only one of the groove types A, B or C or A1, B1 or C1 can be arranged on the key within a line. The different profile types FIGS. 8, 9 can, however, be combined with one another as desired via the different lines along the height of a key.

Due to the asymmetrical arrangement of the grooves within a line, the possibility of variation is considerably increased, since mirror-image use is possible. This ensures that the individual key profiles differ enough from one another to avoid incorrect locking.

10 to 12 show, for example, three different key cross sections with profile arrangements according to the present invention. It should be pointed out again that none of these key profiles can be converted into another profile of the same profile system by any subsequent machining without breaking apart.

The individual profile lines are separated from one another by line spaces 45 in order to provide enough key material between the grooves as profile elements for the ribs which remain in this way. From the second line, the key flat sides 37, 38 run obliquely in the direction of the longitudinal central plane of the key, whereby a so-called. conical profile is provided.

The height of the individual lines can vary along a key height and e.g. remove towards the key chest.

5 to 12, key profiles are drawn in cross section throughout. It goes without saying that such profiles are provided both on the finished key and on the key blank, the finished key being produced from the key blank by milling grooves for the pin tumblers. The design of the key channel profiles of associated locks must also be carried out analogously, as is obvious to a person skilled in the art. The profile arrangement according to the present invention thus relates in the same way to flat keys, key blanks and lock profiles.

In Fig. 12, the key 46 is inserted into the associated key channel 47 of an associated lock, but not shown. A groove in the key corresponds to a correspondingly designed rib of the key channel.

A major advantage of the construction according to the invention is that a large number of individual keys (unique pieces) can be systematically produced. In the exemplary embodiments according to FIGS. 7 to 11, these are approximately 750 key profiles, which differ from one another to a considerable extent, the smallest difference between two key profiles having a sufficiently large cross section, so that there is a high level of security against locking. Previously known key profiles had to make do with about 60 unique profiles. The 750 key profiles mentioned can continue to be increased if more lines are used.

Furthermore, it is pointed out to the advantage that a superordinate key cannot be produced for any of the profile arrangements according to the invention and that the individual unique keys cannot be converted into other keys of the same profile system.

The illustrations in the drawings are purely schematic. In practice, the key cross-sectional shape can be modified according to the requirements. For example, the key back 48 (Fig. 1 and 10 to 12) adapted to the radius of the cylinder core, i.e. be curved in cross section. The incisions 4 for the pin tumblers are located in the area of the key chest (reference number 49 in FIG. 1 and FIG. 10), so that the ribs and grooves of the key profile are omitted at the locations of these incisions, depending on the incision depth.

Claims (8)

1. Flat key for cylinder locks, that has longitudinal grooves (31, 32, 33) on both flat sides, which, starting from a key blank divided into strips, wherein the strip height is determined by the side aperture of the longitudinal groove, are disposed in the strips, wherein in each strip there is a longitudinal groove (31, 32) either on one flat side or on the other flat side or there is a longitudinal groove (33) on both flat sides, characterised in that all grooves (31 to 33) are shaped in accordance with one of three profile types (A, B, C) and all grooves of one profile type (A, B or C) have the same cross sectional shape and the same profile depth (t₁, t₂ or t₃), wherein, given the arrangement of the longitudinal grooves (profile type A, B), which are disposed on one side of the flat side, the profile depth (t₁, t₂) extends from the flat side (37, 38) up to or over the geometrical longitudinal central plane (30) of the key blank and, when the longitudinal grooves are disposed on both sides of the flat sides (profile type C), the profile depth (t₃) is less than the distance from the flat side to the geometrical longitudinal central plane (30), so that when opposed longitudinal grooves (C) are disposed on the two flat sides, these longitudinal grooves are separated by a web, and that the flat key has at least two of the profile types (A, B, C).

2. Flat key according to claim 1, characterised in that the flat key has all three profile types (A, B, C).

3. Flat key according to claims 1 or 2, characterised in that each longitudinal groove of the profile types (A, B and/or C) is unsymmetrical with respect to the plane of symmetry (34) of the strip which bisects the strip and is perpendicular to the longitudinal central plane (30), and variations (A, A1, B, B_i) are formed by rotation around this plane of symmetry of the strip (Figure 8, 9).

4. Flat key according to any of claims 1 to 3, characterised in that, depending on the symmetry position of the variation, the upper or lower groove flank of each longitudinal groove (A, B, C; A₁, B_i, C_i) lies on or approximately on one of the strip diagonals (39, 40).

5. Flat key according to any of previous claims 1 to 4, characterised in that the strip height varies with the key height and decreases to the key breast (49).

6. Flat key according to any of previous claims 1 to 5, characterised in that the flat sides (37, 38) of the key run at an angle to the longitudinal central plane (30) of the key over at least part of their length towards the key breast (49) (conical profile).

7. Flat key according to any of claims 1 to 6, characterised in that the strips are separated from one another by intermediate spaces (45), whereby ribs are formed on the flat key.

8. Cylinder lock with a profiled key slot to accept a flat key according to any of claims 1 to 7, wherein the key slot has ribs on both sides, which are arranged in strips, wherein in each strip a rib is disposed either on one or the other flank or on both flanks, characterised in that all ribs are formed in accordance with one of three profile types (A, B, C) and all ribs of one profile type (A, B, C) have the same cross sectional shape and the same rib height, wherein, given the arrangement of the ribs which are disposed on one side of the flank, the rib height extends from the side of the flank up to or over the geometrical longitudinal central plane of the key slot, and, when opposed ribs are disposed on both flanks, these ribs are separated from one another by an intermediate space, and that at least two of the profile types (A, B, C) are disposed.

Images