Field of the invention

The present invention relates to a lock insert with at least one revolving operating projection for the lock pawl.

Background of the invention

At present the most widely spread lock inserts in the Czech Republic are lock inserts of the system FAB in many modifications. The lock insert is rotatable, i.e. after the appropriate key is inserted, the respective pawls arranged in a row one after another are unlocked, whereafter the appropriate liner may be rotated and entrain an operating projection for a pawl of a door lock. Such an arrangement of a door lock may be easily overcome by a specialist, especially when using sets of various lamellas. To avoid this, some of the modifications of said lock inserts are provided with two rows of pawls. Even such an arrangement does not prevent sufficiently its trespass.

By using brute force it is either possible to break out known lock insert or to drill out a set of its blocking pawls and so on. To decrease the chance of breaking out lock inserts, different massive shields are used on the outside of the system of lock inserts, which avoid breaking out of a lock insert, however they form e.g. a solid hold for extending of the whole door frame.

Further improvements have been designed in the aim to secure the lock insert against breaking out of its rotatable part by a brute force, to make it resistant against unauthorized handling, especially against breaking and drilling out, to prevent its vulnerability to otherwise giving in to brute mechanical interference, to enhance its resistance against objects emulating keys, and to make it impossible to take contingent impresses of the arrangement of the inner locking system and so on. Said aim has been achieved by a lock insert, which consists of a first locking system for the axial contact with the frontal end of the

key, where the first locking system is formed by a bottom of a blocking liner with an axial carrier cavity for the frontal end of the key, the liner being provided on the outside with at least one of said operating projections and in its housing with at least one radial opening for passage of a distance element, and of a second locking system for radial contact with the key, where the second locking system is formed by a hollow unrevolving liner mainly coaxially enclosing on the outside and on the inside said blocking liner and is provided with radially slidable elevation means for each distance element. The disadvantage of this solution consists in the use of a coupling system attached to the blocking liner. During opening the rotatable plate could slip, especially when the mechanism of the mortised lock is damaged or worn out.

Summary of the invention

It is an object of the present invention to create a lock insert, which would be resistant to all attempts of unauthorized handling, especially which could not be broken asunder, drilled out, and which would not otherwise give in to brute mechanical interference, which would be resistant to any object emulating a key, and which would make it impossible to take contingent impresses of the arrangement of the inner locking system and so on. Said object is realized by the lock insert according to this invention, the gist of which is, that the lock insert with at least one rotatable operating projection for a pawl of the lock consists of a first locking system for an axial contact with the frontal end of the key, the first locking system being formed by a blocking liner with a bottom with an axial carrier cavity for the frontal end of the key, the liner being provided on the outside with at least one of said operating projections and in its housing with at least one radial opening with a distance element placed therein, and of a second locking system for the radial contact with the key, the second locking system being formed by a hollow

unrevolving liner coaxially enclosing at least from the outside said blocking liner and being provided with radially slidable elevation means for each distance element, wherein the bottom is firmly connected with the blocking liner.

To make any unauthorized handling with the lock insert according to the invention practically impossible, the radial openings for the distance elements in the housing of the blocking liner are arranged e.g. in a helix, this arrangement corresponding to the arrangement of the slidable radial elevation means in the double housing of the hollow unrevolving liner.

Considering the production, it is advantageous according to the invention, when the distance elements have the form of small balls, the diameter of which comports with the wall thickness of the blocking liner, or the form of cylinders with chamferred edges, the height of which reaches the wall thickness of the blocking liner.

For a reliable and definite function of the lock insert it is advantageous according to the invention, if each elevation means for a distance element consists of a pair of shifting pins, the first shifting pin extending into the cavity of the hollow unrevolving liner, supports the distance element, while the second shifting pin arranged on the other side of the distance element applies a load to it, wherein the heights of all first shifting pins of the distance elements mutually differ.

To increase the resistance of the lock inserts against an unauthorized handling inside, it is expedient according to the invention, if the first shifting pin from the entry side of the lock insert is as high as possible depending on the critical cross-section of the key.

For different ways of usage of the lock insert, it is possible to double the lock insert by a mirror symetrical arrangement of the first locking system and the second locking system and to connect them mutually by an axial connection.

Description of the drawings

Fig. 1 is a longitudinal section of the lock insert, Fig. 2 is a cross-section of the lock insert taken through the first set of the elevation means and distance elements on the entry side of the lock insert for the key, Fig. 3 is a detailed view of the arrangement and realization of the elevation means for the distance elements, Fig. 4 is an outline of the realization of the functional part of the key for operating of the lock insert.

Detailed description of the preferred embodiments

The lock insert with at least one rotatable operating projection l for a not shown pawl of a not shown lock (Fig. 1) , consists of a first locking system 2. for an axial contact with the frontal end 2. of the key 4. and of a second locking system 1Q. for the radial contact with the key 4_. The first locking system is formed by a bottom 5. of a blocking liner 7. with an axial carrier cavity £ for the frontal end i of the key 4.. The liner 2 is provided on the outside with at least one said operating projection l and in its housing with at least one radial opening JB. for the passage of a distance element 2.. The second locking system 1Q. is formed by a hollow unrevolving liner H mainly coaxially enclosing by its large cylindrical annulus 111 from the outside and by its small cylindrical annulus 12 from the inside said blocking liner 2- The hollow unrevolving liner H is provided with radially slidable elevation means 12. for each distance element 2..

The radial openings jj. for distance elements 2. are arranged in the housing of the blocking liner 1, e.g. in a helix, said helix arrangement corresponding to the arrangement of the radial slidable elevation means ___. in the double housing of the hollow unrevolving liner 11. A longitudinal arrangement of the radial openings fi including all its fittings is apparent e.g. from the dot-and-dashed lines ___. -

The distance elements 2. have the form of small balls, the diameter of which comports with the wall thickness of the blocking liner 2# or the form of not shown cylinders with chamfered edges, the height of which reaches the wall thickness of the blocking liner 2-

The slidable elevation means 12 for each distance element 2. in the preferred embodiment consists of a pair of shifting pins 2__S_, 121- The first shifting pin 120 extends into a cavity of the hollow unrevolving liner H and supports the distance element 2., while the second shifting pin 121/ arranged on the other side of the distance element 2., applies a load to it, wherein the heights of all first shifting pins 12Ω. and of the distance elements 2. mutually differ. As it will be disclosed further on, it is expedient, that the first shifting pin 120 from the entry side of the lock insert is as high as possible, as it is displayed in detail in Fig. 3, where also one of possible embodiments of the shifting pin 121 loaded by a spring 12,3 is specifically marked out, the spring 123 being arranged under a plug 124. The free frontal end of the first shifting pin 120. extending into the cavity of the small cylindrical annulus 112 of the hollow unrevolving liner H, is adjusted to the form of a spherical cap or a truncated cone and so on.

The blocking liner 2 and the hollow unrevolving liner 11 are axially mutually connected. Implementation of said connection is effected e.g. by means of a packing piece 16, which is fastened to the rear face of the unrevolving hollow liner H and extends into the circumferential groove 17. formed on the outer surface of the blocking liner 2-

The lock insert may be doubled by adding a second locking system 2. to the described first locking system 2 in a mirror arrangement, both systems 2 and 113. being mutually connected by a not shown axial connection.

A uniform key 4. for the described lock insert is of a rotary configuration, the functional side of which consists of said frontal end 2, corresponding to the shape of the axial carrier cavity ξ_ in the rotatable plate £, said

functional side having the form of a truncated cone 4J1 for the radial contact with the second locking system ___., while said truncated cone ___ is provided with one or more circumferential conical recessions 41 or stages for radial shifting and implementation of the appropriate terminal lift of the slidable elevation means 12 of the distance elements 2. in the radial openings £. of the blocking liner 2.

The function of the lock insert according to the invention is as follows:

The appropriate key 4. (Fig. 4) , being inserted with its frontal end 2. in the axial direction into the cavity of the small cylindrical annulus 112 of the hollow unrevolving liner H, gradually, in consequence of the conical and eventually gradual form of its functional side, radially pulls apart the slidable elevation means 12 of the distance elements 2. in the radial openings £ in the housing of the blocking liner 2 into various positions, while however, not all distance elements 2. get into the positions, where their appropriate tangents would fit with the surfaces on the inner and outer side of the housing of said blocking liner 2. This happens after the key 4 is fully inserted following its appropriate angular turning and fitting with its frontal end 2. into the axial carrier cavity £ in the bottom 5. of the blocking liner 2. If the appropriate key 4 is used, then, not until reaching this position, said elevation means 12 get into the beforehand determined positions, by which the distance elements 2., which are operated by them, are placed in the radial opening precisely lined-up with the thickness of the housing of the blocking liner 2. The adjacent faces of the first shifting pins 120 and the second shifting pins 121 of the elevation means 12, adjacent to the distance elements 2, are positioned in this way towards the surfaces of said housing of the blocking liner 1_ . Thereby, the blocking liner 2 is unblocked, because neither said adjacent ends of the first shifting pins 12Ω. nor the ends of the second shifting pins 121/ which previously acted as arresting elements against turning of the blocking liner 1,

are in an engagement with the radial openings £ for the distance elements 2. -

By turning of the key 4. the torque is transferred from its frontal end 2 to the bottom ϋ of the blocking liner 2 by means of the axial carrier cavity £. If the distance elements 2. and the adjacent first shifting pins 120 and the second shifting pins 121 are in the due positions, the blocking liner 2 may rotate together with the operating projection 1 and through this projection 1 affect the not shown lock pawl. Hereby the first shifting pins 120 and the second shifting pins 121 of the elevation means 12 only slide on the walls of the housing of the blocking liner 2 and after passing by any of the radial openings £ they remain henceforth in an adequate distance according to the distance elements 2. centered in the radial openings f_ .

If the above described state for operating the lock insert is not achieved, e.g. when using inappropriate key 4, then the slidable elevation means 12 of the distance elements ≤. remain in the position, in which either the first shifting pins 120 or the second shifting pins 121 of the slidable elevation means 12 remain fitted in the radial openings £ and henceforth act as an obstacle against turning of the blocking liner 2- In that case, although the engagment of the frontal end 2. of the key 4 or of its substitute with the axial carrier cavity £ is achieved, the blocking liner 2 with the operating projection 1 will not be turned.

On an attempt to operate the lock insert by using an arrangement of various jigs, insuperable difficulties arise, especially because the first shifting pins 12_ of the slidable elevation means 12 of the distance elements 2. are seated in a helix or otherwise and because they are not lined-up. If, as indicated above, the first shifting pin 120 from the entry side of the lock insert is as high as possible, what corresponds e.g. also to the appropriate cross-section of the recession 41 of the functional side of the key 4., said arrangement results in a substantial

narrowing of said entering opening for a possible unauthorized handling inside the lock insert.