EP1931843B1 - Locking device - Google Patents

Abstract

The invention relates to a locking device (1) comprising a base body (2) and a locking element (4) that can be displaced along a separating plane (8) in relation to the base body and can be stopped by at least one locking rod (12) received in a borehole (10), said locking rod comprising a central upper rod (16) that can be displaced in the locking element (4), inside the borehole (10), in relation to the separating plane (8), a coaxial upper sleeve (18) guiding said upper rod, and a lower sleeve (22) which is subjected to a first elastic force in the direction of the separating plane (8) by means of first elastic means (20). The upper sleeve (18) and the lower sleeve (22) can be displaced from a locking position into a release position, in relation to the separating plane (8), by inserting a key-side closing rod (24) into the borehole (10), enabling the facing front surfaces of the lower sleeve (22) and the upper sleeve (18) to extend in the region of the separating plane (8) in said release position in order to release the displacement of the locking element (4). The invention is characterised in that, when the key-side closing rod (24) is inserted, the central upper rod (16) is displaced by a magnetic force action, in relation to the separating plane (8), in order to release the displacement of the locking element (4).

Description

The invention relates to a locking device, in particular in the form of a protective fitting or a lock, comprising a key according to the preamble of claim 1.

In the field of security and locking technology locking devices in the form of protective fittings and locks are used in a known manner, which have a, for example, attached to a door of a building body on which a locking element in the form of a protective cover made of hardened material is slidably received in sliding guides, to cover an opening formed in the main body for a known lock cylinder or the like and thereby protect it against mechanical manipulation. The locking of the locking element takes place via spring-loaded locking pins which are movably received in a bore in the locking element and in the base body, and displaced by inserting a key-side locking pin to release the lock in such a way that the adjacent end faces of the locking pins in the between the body and the locking element extending parting plane lie.

Such a protective fitting according to the preamble of claim 1, wherein the locking pins are additionally guided in spring-loaded lower and upper sleeves, is from the EP 0 367 000 B1 known. Through the use of lower and upper sleeves to guide the locking pins, the number of possible locking combinations compared to the aforementioned locking devices with easily guided locking pins is significantly increased in this protective fitting and accordingly improves the protection against manipulation.

Accordingly, it is the object of the present invention to provide a locking device in which the manipulation protection and the number of locking combinations over the prior art is increased again.

This object is achieved by the features of claim 1.

According to the invention, a locking device, in particular in the form of a protective fitting or lock on a base body, relative to which a locking element, eg the protective cover of the protective fitting or the bolt of a door or window mounted lock, or the U-shaped bracket in the case in the DE 20 2004 004 024 U1 described padlock, etc., is movable in sliding guides along a parting plane.

The locking element is thereby arrested by at least one locking pin received in a bore, which acts in the locking element within the bore relative to the parting plane central top pin, a leading this coaxial upper sleeve and a first resilient means towards the parting plane out with a first resilient force Lower sleeve includes.

The upper sleeve and the lower sleeve are movable by inserting a key-side locking pin into the bore from the outside of the locking member relative to the parting plane from a locking position to a release position, in which in the locked state adjacent end faces of the lower sleeve and upper sleeve to release the movement of the locking element run in the region of the parting line.

The invention is characterized in that the central upper pin is moved relative to the parting plane inserted into the bore schlüsselseitigem closing pin to release the movement of the locking element by a magnetic force generated between the locking pin and the central top pin to completely cancel the locking of the locking element. Here, the magnetic force may have a key-side closing pin and the upper pin each other attractive or repulsive effect, in which the upper pin with inserted schlüsselseitigem lock pin in the direction of the parting plane or is moved away from it, wherein the effect of the magnetic force is particularly dependent on the polarization of the underlying magnetic field.

By the invention there is the advantage that due to the increased number of locking combinations, characterized by the additional use of a magnetic interaction between the guided in the upper sleeves of the movable locking elements locking pins - hereinafter referred to as central upper pins - and the associated, to open the locking device used key-side locking pins, the number of locking pins to be used in a locking device can be reduced overall. As a result, the mechanical complexity in the production of protective fittings, or even mechanical locks, in which the locking element, for example, the function of a cross bar, or in padlocks, as in the example DE 20 2004 004 024 U1 significantly reduced by using fewer locking pins.

Accordingly, with a predetermined number of locking pins, the number of locking combinations - and thus the manipulation security - desired case, increase in the same way.

According to a first preferred embodiment of the invention, the key-side locking pin has first magnetic means and the central upper pin second magnetic means which generate a magnetic force attracting the first magnetic means. The central top pin is thereby connected via second elastic means, e.g. a known helical compression spring, in the direction of the parting plane towards a second resilient force is applied, which has such a size that the central top pin is moved with inserted schlüsselseitigem closing pin by the attractive magnetic force against the force of the second resilient means from the parting plane.

Although the first and second magnetic means can be created by permanent magnets attached to the striker pin and the central top pin respectively, it is the same conceivable, at least one of the pins, preferably the mechanically less heavily loaded key-side locking pin, even from a ferromagnetic material, for example made of iron to manufacture, which is imparted from the outset, the required magnetization, whereas the central top pin also made of only a magnetizable, in particular ferromagnetic material may exist, which itself has no own permanent magnetic field, but only by the resulting polarization in the presence of the magnetic field of the key-side locking pin undergoes an attraction.

This embodiment of the invention offers the advantage that by simultaneously providing key-side locking pins with a "north-south", "south-north" or no polarization on a key and a correspondingly designed polarization of the central upper pins increase the number of locks considerably leaves.

Furthermore, in this embodiment of the invention, a collar may be formed on the central upper pin on which the second resilient means, which urge the upper pin in the direction of the parting plane, are supported. Furthermore, it can be provided here that the lower sleeve has a smaller inner diameter than the upper sleeve, and that the central upper pin is supported on the collar on the lower sleeve, whereby the manufacture of the device is considerably simplified, since no additional lower pin is required on the the upper pin is supported by its end face.

Alternatively, it may be provided according to a further embodiment of the invention that at the separation plane far end of the coaxial upper sleeve, a stop is formed, on which the collar of the central upper pin to limit the displacement movement of the central upper pin in the coaxial upper sleeve is supported, if For example, the upper pin is urged in its direction by the magnetic interaction with the key-side locking pin.

According to a further advantageous embodiment of this embodiment of the invention, which provides increased security against manipulation, a central lower pin is slidably received in the lower sleeve, by third elastic means, in particular a spiral compression spring, toward the central upper pin out with a third resilient force is charged.

According to a further idea underlying the invention, a key adapted to the diameter of the central upper pin is formed on the key-side closing pin, which extends into the interior of the coaxial upper sleeve when the key-in closing pin is inserted. The projection serves as a stop for the central upper pin on which in the release position, the key-side closing element facing end face of the central upper pin abuts directly, wherein the separating-plane-side end face of the central upper pin is in contrast in the parting plane. This results in the advantage that by choosing the length of the projection, which preferably consists of permanent magnetic material, in addition a further number of closures or combination options is obtained, which again improve the manipulation protection.

According to another embodiment of the invention, the key-side locking pin has first magnetic means and the central top pin second magnetic means in the form of permanent magnets which generate a magnetic force repelling the first and second magnetic means. In addition, in the lower sleeve, cooperating with the central upper pin, central lower pin is slidably received, which is urged by third resilient means, for example in the form of a correspondingly configured spiral compression spring in the direction of the central upper pin. By inserting the key-side closing pin of the central upper pin and thus also the voltage applied to this central lower pin within the bore is moved in such a way that the separating-plane-side end faces of the lower and upper pin come to lie in the region of the parting plane and release the locking element. It may be advantageous if the edges of the separating-plane-side end faces of the central The bottom pin and / or the central top pin are chamfered or bevelled, as a reliable release of the locking element is even guaranteed even if the position of the end surfaces of the lower pin and / or upper pin due to friction or a certain variation of the size of the acting magnetic force is not accurate corresponds to the position of the parting plane.

In this case, it may further be advantageous to avoid contamination when the coaxial upper sleeve is closed at its end remote from the parting plane by a closure element, which preferably consists of a non-magnetic material, in particular of non-magnetic steel, and preferably in one piece or integral to reduce manufacturing costs is formed with the coaxial upper sleeve.

According to a further advantageous embodiment of this embodiment of the invention, the movement of the central lower pin away from the parting plane can be limited by a further stop, whereby a reliable guidance of the central lower pin is ensured within a predetermined axial range.

According to a further embodiment of the underlying principle of the invention, the key-side locking pin comprises first magnetic means and the central top pin second magnetic means which cooperate in such a way with the first magnetic means that the central top pin by inserting the key-side locking pin in the bore of a the movement of the locking element preventing circumferential locking position is rotated in a displacement of the locking element enabling circumferential release position. The first and second magnetic means are preferably designed as permanent magnets which have a perpendicular to the longitudinal axis of the bore polarization, wherein in the release position of the central upper pin the polarization direction of the provided on the key-side closing pin permanent magnet preferably rotated by 90 ° or 180 ° to Polarization of the magnet provided on the upper pin runs.

According to the preferred embodiment of this principle according to the invention, a nose-like projection is provided on the separating-side end face of the central upper pin, which extends into the coaxial lower sleeve in the peripheral blocking position of the central upper pin over the dividing plane and under the locking element in the release position of the coaxial upper sleeve Generation of a positive connection locked against displacement along the parting plane. For this purpose, in the simplest case in the circumferential locking position extending parallel to the longitudinal axis of the bore extending, not bevelled portion of the peripheral surface of the central upper pin on the inner edge of the lower sleeve and thereby prevent displacement of the locking element, whereas in the circumferential release position, a second beveled section, the opposite to the first section, for example may be arranged rotated by 90 °, rests upon rotation of the upper pin as a result of the magnetic force at the edge of the lower sleeve, and allows a displacement of the upper pin of the parting plane due to the bevel. In this case, the chamfer preferably includes at least an angle of 45 ° with the longitudinal axis of the bore, so that during the displacement of the upper pin, the chamfer pushes over the edge of the lower sleeve and forces the upper pin out of the parting plane.

Advantageously, according to a further embodiment in the coaxial lower sleeve, a central lower pin with a further nose-like projection is slidably and rotatably received, which is acted upon by second resilient means in the direction of the central upper pin with a second resilient force, wherein the nose-like and the other nose-like projection are configured in such a way that in the circumferential locking position of the central upper pin, the tips of the nose-like and other nose-like projection and the opposite these axially recessed faces of the central lower pin and central upper pin tooth-like mesh. In contrast, are after turning the central upper pin in the circumferential release position of the upper pin only the tip of the nose-like projection of the upper pin and the tip of the nose-like projection of the Sub-pin in the region of the parting plane to each other, whereby a displacement of the locking element along the parting plane is made possible.

The nose-like projection and / or the further nose-like projection preferably have a continuous rising from the associated axially recessed face from the tip of the projection rising sliding surface, which preferably extends in the circumferential direction, in particular helical over an angular range of 90 ° or 180 °. The direction of rotation of the sliding surfaces of the nose-like projection and the further nose-like projection are in this case correspondingly opposite.

Further features of the invention are contained in the subclaims.

The invention will be described below with reference to the drawings based on preferred embodiments.

In the drawings show:

Fig. 1

a schematic representation of a configured as a security fitting inventive locking device with a plurality of locking pins and an indicated key with a plurality of key-side locking pins,

Fig. 2a

a schematic side view of a first embodiment of the locking device according to the invention, in which only a central upper pin is used, which is moved by an attractive magnetic force action between the upper pin and schlüsselseitigem lock pin in the release position, in the locked position,

Fig. 2b

the embodiment of Fig. 2a in the release position with inserted key or key-side locking pin,

Fig. 3a

a further embodiment of the locking device according to the invention, in which compared to the embodiment of Fig. 2a and 2b the upper pin consists only of a magnetizable, but not permanently magnetic material, and additionally a central lower pin is used, in the locked position,

Fig. 3b

the embodiment of Fig. 3a in the release position with inserted key or key-side locking pin,

Fig. 4a

a further embodiment of a locking device according to the invention, in which the central upper pin is actuated by a repulsive magnetic force action between schlüsselseitigem lock pin and upper pin, in the locked position;

Fig. 4b

the embodiment of Fig. 4a in the release position with inserted key or key-side locking pin,

Fig. 5a

a further embodiment of the locking device according to the invention, in which the central upper pin is rotated by the magnetic force action from a circumferential locking position to a circumferential release position, in the locked position,

Fig. 5b

the embodiment of Fig. 5a with an inserted authorized key or key-side locking pin after rotating the upper pin in the circumferential release position, and

Fig. 5c

the embodiment of Fig. 5a and 5b with an inserted unauthorized key-side locking pin in which the required for rotating the central upper pin key-side permanent magnet is missing and the upper pin is in the circumferential locking position and locks the locking element.

As in Fig. 1 is shown, a locking device 1 according to the invention in the form of a protective fitting shown a base body 2, relative to which a locking element 4 in the form of a protective cover shown in guides 6 along a parting plane 8 is movable to release the access to a known lock cylinder 9 through an opening 14 formed in the housing of the main body is accessible through when the locking element in the in Fig. 1 is shown release position.

The locking element 4 can be locked by at least one received in a bore 10 locking pin 12, which in detail in the FIGS. 2a to 5c is shown in various embodiments, and the one in the locking element 4 within the bore 10 relative to the parting plane 8 displaceable central upper pin 16, a leading this coaxial upper sleeve 18 and a first resilient means in the form of a spiral compression spring 20 toward the parting plane 8 out with a first spring-elastic force acted upon lower sleeve 22 includes.

The upper sleeve 18 and the lower sleeve 22 are by inserting a key-side locking pin 24 into the bore 10 from the outside of the locking element 4 forth relative to the parting plane 8 of a in the FIGS. 2a . 3a . 4a and 5a shown locking position in a in the FIGS. 2b . 3b . 4b and 5b shown release position movable in which lie in the locked state adjacent, unspecified end faces of the lower sleeve 22 and upper sleeve 18 in the region of the parting plane 8 and a displacement of the locking element 4 in the in Fig. 1 allow shown position.

Like the presentation of Fig. 1 can be removed, are preferably provided on the locking device 1 more locking pins 12 in a corresponding number of holes 10, which are actuated simultaneously by a corresponding number of appropriately designed key-side locking pins 24 having key 28. This can not only uniform on a key 28 configured key-side locking pins 24 a single in the Fig. 2 to 5 embodiment shown, but it is also possible to increase the number of locking combinations, two or more of the in the FIGS. 2 to 5 shown embodiments of key-side locking pins 24 at the same time to be arranged in combination on a key 28 to actuate a corresponding number of correspondingly differently designed locking pins 12 on the locking device 1.

According to a first, in Fig. 2a and 2b shown embodiment of the invention, the key-side closing pin 24 has first magnetic means in the form of a perpendicular to the separation plane 8 polarized permanent magnet 30. At the central top pin 16 second magnetic means in the form of a second permanent magnet 32 are arranged by gluing a piece of permanent magnetic material or by polarizing of the central top pin 16, and which has a polarization opposite the first magnet 30, so that between the magnets 30, 32 an attractive magnetic force acts, the central top pin 16 against the force of a second spiral compression spring 36, the preferably on a collar 38 of the upper pin 16 and a preferably circumferential upper stop 45 of the upper sleeve 18 is supported, moved away from the parting plane 8, when the key-side locking pin 24, as in Fig. 2b shown in the hole 10 is inserted. The lengths of the upper and lower sleeves 18, 22 and the central upper pin 16 are adapted to the penetration depth of the key-side locking pin 24 in such a way that the adjacent end faces of the upper and lower sleeves 18, 22 lie in the parting plane 8, and the separating plane side End of the central upper pin 16 extends above the dividing plane 8 in order to unlock the locking element 4 and to move in the direction of the arrow 34 can.

By an appropriate alternating polarization "north-north" or "south-south", the first and second magnets 30, 32 can be obtained when using multiple locking pins 12, an additional number of combination options. Furthermore, it can be at the in Fig. 2a and 2b shown embodiment of the invention be advantageous if the lower sleeve 22 has a smaller inner diameter than the upper sleeve 18, so that the central top pin 16 in the in Fig. 2a shown locking position on the collar 38 can be supported on the lower sleeve 22. In addition, it is advantageous if the upper sleeve 18 is closed to the outside by a closure element in the form of a cap 42 made of non-magnetic or diamagnetic material to prevent the ingress of dirt and also to conceal the insight into the interior of the upper sleeve 18 , or to protect them against mechanical manipulation.

In the in the FIGS. 3a and 3b shown embodiment of the invention, in addition a central lower pin 40 is received in the lower sleeve 22, which is urged by third elastic means in the form of a third helical compression spring 44 against the central upper pin 16, which consists of a hardened, magnetizable material, and by the first key-side permanent magnet 30 is tightened. In this embodiment of the invention, the first permanent magnet 30 has an additional projection 46, which has a length matched to the length of the central upper pin 16, so that the axial end face of the central upper pin 16 and of the central lower pin 40 run exactly at the level of the separating plane 8 when the key-side locking pin 24 is inserted into the bore 10, as shown in FIG Fig. 3b is shown.

As based on the FIGS. 3a and 3b can be seen, the Oberhülse18 and / or in the same way the lower sleeve 22 desired case may be made in two parts to allow production in the first place when one of the sleeves receives resilient means which are supported within the sleeve on a collar 38 as in the embodiments of Fig. 2 and 3 the case is. The displacement of the central upper pin 16 in the direction of the central lower pin 40 is in this case limited by a lower stop 43, which may be assigned to the lower or upper sleeve 18, 22.

At the in Fig. 4a and 4b shown embodiment of the invention, a central lower pin 40 is also received in the lower sleeve 22, and the upper pin 16 inside the upwardly closed by a cap upper sleeve 18 with a parallel to the longitudinal axis of the bore 10 polarized second permanent magnet 32 is provided, the polarization direction of the polarization direction of the first lock pin side Permanent magnet 30 is directed counter to, so that between the central upper pin 16 and the key-side closing pin 24, a repulsive magnetic force is generated, which drives it into the bore 10. The central upper pin 16 has a length such that the repulsive magnetic force of the separating plane side end of the same moves into the region of the parting plane 8 when the key-side locking pin 24 is fully inserted into the bore 10, wherein at the lower end of the central lower pin 40 a stop 41 may be provided, which limits the movement of the central lower pin 40 away from the parting line 8, as shown in FIG Fig. 4b is shown. In this case, the edges of the central lower pin 40 and / or also of the central upper pin 16 can have a chamfer 48 in order to reliably ensure the unlocking even with a slightly fluctuating magnetic force.

As in the FIGS. 5a to 5c is shown, the locking device 1 according to the invention according to a further embodiment of the separating-side end face of the central upper pin 16 a nose-like projection 50 with a chamfer in the form of a steadily increasing sliding surface 52. At the central lower pin 40, which is urged by the third coil spring 44 in the direction of the upper pin 16, a further nose-like projection 54 is formed, which has a chamfer 56 in the form of a continuous rising to the top 68 of the central lower pin 40 sliding surface. The nose-like projections 50 and 54 are designed to be complementary to each other in such a way that these in the in Fig. 5a shown position tooth-like mesh.

Like that FIGS. 5a to 5c can be removed, the upper sleeve 16 on its outer side a projection 58 which is guided in a longitudinal groove 60 in the locking element 4 in order to prevent a circumferential rotation of the upper sleeve 18.

As should be indicated by the dashed lines, in the inner peripheral surface of the upper sleeve 18 is formed by a 180 ° circumferential circumferential groove 62 which receives a arranged on the central upper pin 16 projection 64, and forms a stop when the upper pin 16 from its in Fig. 5a and 5c shown circumferential Locking position by inserting an authorized key-side closing element 24 in the in Fig. 5b shown circumferential release position is rotated in which the tips 66 and 68 of the nose-like projections 50 and 54 lie on each other. The rotation of the upper pin 16 from the circumferential locking position to the circumferential release position is effected by the circumferential offset of the first key-side permanent magnet 30 relative to the second upper-pin-side permanent magnet 32, which in the embodiment of Fig. 5 in the range of 180 °.

As already in the Fig. 4a to Fig. 4b shown embodiment of the invention can also in Fig. 5a to Fig. 5c shown central lower pin 40 have arranged at the lower end stop 41, which - as in Fig. 5b is shown - the displacement movement of the central lower pin 40 is bounded away from the parting plane.

Finally shows Fig. 5c the case that a manipulated key with a the lower and upper sleeve 22, 18 displaced into the release position sizing is inserted into the bore 10, but which has no first permanent magnet 30, which leads to a rotation of the upper pin 16 in the circumferential release position of Fig. 5b leads. In this case, the locking of the locking element 4 is obtained by the further nose-like projection 54 of the lower pin 40, which extends beyond the parting plane 8 addition.

reference numeral

1

Locking device / security fitting

2

body

4

Locking element / protective cover

6

guides

8th

parting plane

9

lock cylinder

10

drilling

12

locking pin

14

Opening in the body

16

central top pin

18

coaxial upper sleeve

20

first elastic means

22

lower sleeve

24

key-side locking pin

28

key

30

first permanent magnet

32

second permanent magnet

34

arrow

36

second elastic means

38

collar

40

central lower pin

41

attack

42

Closing member / cap

43

bottom stop

44

third elastic means

45

upper stop

46

head Start

48

chamfer

50

nose-like projection

52

Bevel / slide

54

another nose-like projection

56

Bevel / slide

58

head Start

60

longitudinal groove

62

circumferential groove

64

head Start

66

Tip of the nose-like protrusion

68

Top of the further nose-like protrusion

Claims (17)

1. Locking device (1) comprising a key (28) with a key-side closing rod (24) and a base body (2) and a locking element (4) that can be displaced along a separating plane (8) in relation to the base body and can be stopped by at least one locking rod (12) received in a borehole (10), said locking rod comprising a central upper rod (16) that can be displaced in the locking element (4), inside the borehole (10), a coaxial upper sleeve (18) guiding said upper rod, and a lower sleeve (22) which is subjected to a first elastic force in the direction of the separating plane (8) by means of first elastic means (20) whereby the upper sleeve (18) and the lower sleeve (22) can be displaced from a locking position into a release position, in relation to the separating plane (8), by inserting a key-side closing rod (24) into the borehole (10), enabling the facing front surfaces of the lower sleeve (22) and the upper sleeve (18) to extend in the region of the separating plane (8) in said release position in order to release the displacement of the locking element (4),
   characterised in that
   when the key-side closing rod (24) is inserted into the borehole (10), the central upper rod (16) is displaced in relation to the separating plane (8) in order to release the displacement of the locking element (4) by a magnetic force action which is generated between the closing rod (24) and the central upper rod (16).
2. Locking device in accordance with claim 1,
   characterised in
   that the key-side closing rod (24) has a first magnetic means (30), that the central upper rod (16) has second magnetic means (32) which generates a magnetic force that attracts the first magnetic means (30), and that the central upper rod (16) is subject to a secondary elastic force through secondary elastic means (36) towards the separating plane (8) such that, when the key-side closing rod (24) is inserted, the central upper rod (16) is displaced outwards out of the separating plane (8) by the attracting magnetic force against the force exerted by the secondary elastic means (36).
3. Locking device in accordance with claim 2,
   characterised in
   that a collar (38) is formed on the central upper rod (16).
4. Locking device in accordance with claim 3,
   characterised in
   that the internal diameter of the lower sleeve (22) is smaller than the central upper sleeve (18), and that the central upper rod (16) is supported on the lower sleeve (22) by the collar (38).
5. Locking device in accordance with claim 3,
   characterised in
   that an upper stop (45) is provided on the end of the coaxial upper sleeve (18) away from the separating plane (8), on which stop the collar (38) of the central upper rod (16) rests to restrict the translational motion of the central upper rod (16) in the coaxial upper sleeve (18).
6. Locking device in accordance with one of the preceding claims,
   characterised in
   that a central lower rod (40) fits displaceably into the lower sleeve (22) and is subject to a third elastic force by a third elastic means (44) towards the central upper rod (16).
7. Locking device in accordance with one of the preceding claims,
   characterised in
   that a lug (46) fitting the diameter of the central upper rod (16) is formed on the key-side closing rod (24) whereby, when the key-side closing rod (24) is inserted, said closing rod extends into the internal space of the coaxial upper sleeve (18) and serves as a stop for the central upper rod (16).
8. Locking device in accordance with claim 1,
   characterised in
   that the key-side closing rod (24) has first magnetic means (30), that the central upper rod (16) has second magnetic means (32) which generate a magnetic force that repels the first magnetic means (30), and that in the lower sleeve (22) a central lower rod (40), interacting with the central upper rod (16) and subject to a third elastic force through third elastic means (44), is enclosed to displace towards the central upper rod (16), so that when the key-side closing rod (24) is inserted, the central lower rod (40) is displaced from the separating plane (8) against the action of the third elastic force by the repelling magnetic force.
9. Locking device in accordance with one of the preceding claims,
   characterised in
   that the coaxial upper sleeve (18) is closed off by a closure element (42) at its end furthest from the separating plane (8).
10. Locking device in accordance with claim 9,
    characterised in
    that the closure element (42) consists of a material of low magnetisability, in particular nonmagnetic steel.
11. Locking device in accordance with claim 10,
    characterised in
    that the closure element (42) is formed to be integral with the coaxial upper sleeve (18).
12. Locking device in accordance with claim 6 and, if necessary, with one of claims 7 to 11,
    characterised in
    that the displacement of the central lower rod (40) away from the separating plane (8) is restricted by a further stop (41).
13. Locking device in accordance with claim 1,
    characterised in
    that the key-side closing rod (24) has first magnetic means (30), and that the central upper rod (16) has second magnetic means (32) which interacts with the first magnetic means (30) such that, by inserting key-side closing rod (24) into the borehole (10), the central upper rod is rotated from a totally locking position, arresting the locking element (4), to a totally released position, allowing displacement of the locking element (4).
14. Locking device in accordance with claim 13,
    characterised in
    that a lug-shaped extension (50) is provided on the separating plane-side surface of the central upper rod (16), whereby, with the latter rod in its totally locking position, said extension extends beyond the separating plane (8) into the lower sleeve (22) and arrests the locking element (4) in the release position of the coaxial upper sleeve (18) by creating a positive fit against displacement along the separating plane (8).
15. Locking device in accordance with claim 14,
    characterised in
    that the lug-shaped extension (50) has a sliding surface (52) rising continuously from the axially receding surface of the extension towards the tip (66) of the extension.
16. Locking device in accordance with one of claims 14 or 15,
    characterised in
    that in the lower sleeve (22) a central lower rod (40) with a further lug-shaped extension (54) is displaceably and non-rotationally enclosed which is subject to an elastic force through elastic means (44) towards the central upper rod (16), whereby the lug-shaped and further lug-shaped extensions (50, 54) are arranged such that, in the totally locked position of the central upper rod (16), the tips (66, 68) of the lug-shaped and further lug-shaped extensions (50, 54) and the axially receding surfaces of the central lower rod and central upper rod opposite them engage together as teeth and, in the totally released position of the central upper rod (16), the tips (66, 68) of the projections (50, 54) abut each other in the region of the separating plane (8).
17. Locking device in accordance with claim 16,
    characterised in
    that the further lug-shaped extension (54) has a sliding surface (56) rising continuously from the axially receding surface to the tip (68) of the extension.

Images