AU711775B2

AU711775B2 - Lock bolt

Info

Publication number: AU711775B2
Application number: AU65622/96A
Authority: AU
Inventors: Ernst Keller
Original assignee: Keso AG
Current assignee: Assa Abloy Schweiz AG
Priority date: 1995-09-15
Filing date: 1996-09-13
Publication date: 1999-10-21
Anticipated expiration: 2016-09-13
Also published as: DE59611085D1; AR003593A1; EP0763639B1; ES2227576T3; ATE276416T1; EP0763639A1; BR9603762A; AU6562296A

Description

Our Ref: 609728 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): Address for Service: Ernst Keller Untere Schwandenstrasse 22 CH-8805 Richterswil

SWITZERLAND

DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Invention Title: Lock bolt The following statement is a full performing it known to me:description of this invention, including the best method of 5020 LOCK BOLT The invention relates to a lock bolt for a rotary closure cylinder of a safety lock, having a bolt tip and a bolt head whose back end is intended to rest against a housing pin for the insertion of this pin.

Lock bolts of this kind have been known for a long time. They are also called core pins and in a rotary closure cylinder, form the part of the tumblers that is supported in a radial stepped bore of the rotor. Lock bolts of this kind have been disclosed for example in the applicant's WO 87/05654. These each have a sleeve-shaped slider element that makes it difficult to immobilise the lock bolt when attempting to damage it. The security of rotary closure cylinders is also impaired by so-called "electropicks". With these, a tool is used to spin the rotor around its rotational axis with a particular torque and at the same time, the tumblers are moved radially outward by means of vibration until all of the housing pins are disposed behind the shoulder formed by the rotation of the rotor and Sothe rotor is then released for rotation. Unauthorised unlocking attempts of this kind 15 impair the unlocking security of rotary closure cylinders. Unlocking security is understood by one skilled in the art to mean the degree of difficulty involved in circumventing the tumblers of a rotary closure cylinder using devices, without force, without knowledge about the affiliated key, and without destroying the lock.

According to one aspect of the present invention there is provided a lock bolt for a safety oooo 20 lock, the safety lock including a closure cylinder, a rotor mounted for rotation relative to the closure cylinder the rotor including a key channel, a housing pin mounted to the :oo: cylinder for movement relative to the rotor between a release position in which it permits S° relative rotational movement between the cylinder and the rotor and a retention position So: in which relative rotation between the cylinder and rotor is inhibited, and a housing spring urging the pin into the retention position, the lock bolt including a bolt head operatively mounted to the rotor when in use, and movable relative thereto, the bolt head being arranged in operative abutting relation to the housing pin so that movement thereof can move the housing pin into the release position, the lock bolt further including, a bolt tip operatively carried by the bolt head for limited movement relative thereto between extended and retracted positions, the bolt tip when in use and in the extended position extending into the key channel, spring means urging the bolt tip into the extended p:\wpdocs\map\speci\609728. 11o 3 88 position the arrangement being such that at least initial movement of the bolt tip from the extended position towards the retracted position is relative to the bolt head.

Advantageous improvements ensue from the dependent claims and the description that follows, as well as the drawings.

An exemplary embodiment of the invention is explained in detail below in conjunction with the drawings.

Fig. 1 shows a longitudinal section through a lock bolt according to the invention, Fig. 2 shows a view of a part of the lock bolt, Fig. 3 shows a section through the bolt head, and Fig. 4 shows a section through the bolt tip.

:i The lock bolt 1 shown in the drawing has a bolt head 3 in which a bolt tip 2 and a pin 15 9 are supported so that they can slide. The bolt tip 2 has a peg-shaped projection 16 at which it can be longitudinally slid in a limited fashion in a longitudinal bore 5 of the bolt head 3. A compression spring 8 is supported against the bolt head 3 and against a back end 19 of the bolt tip 2 and secures the tip 2 in the outer position shown, which is *o "defined by a stopping of an annular projection 7 against a shoulder 17. The shoulder 17 20 is constituted by an annular recess 6 on the inside of the bore 5. From the outer position shown the bolt tip 2 can be slid into the bore counter to the opposing force of the spring S. 8, until the back end 19 of the tip 2 is stopped against the bottom 21 of the bore 4. The ~force of the spring 8 is significantly less than the force of the standard housing spring, not shown here, which acts upon the back end of the associated housing pin.

According to Fig. 3, the bolt head 3 has four slots 15 that form radially elastic tabs so that the bolt tip 2 can be inserted into the bolt head 3 and is connected to it in captive fashion. When the bolt tip 2 is inserted into the bore 5, the annular projection 7 engages in detent fashion in the recess 6 by spreading the tabs 20. The bolt tip 2 is thus securely held in the bolt head 3 and furthermore, a simple assembly is possible and can be automated.

ii p:\wpdocs\map\speci\609728.1 1o -3- A blind bore 12 is let into the peg-shaped projection 16 on the back end; a pin 9 that is supported in another bore 11 of the bolt head 3 engages in this blind bore 12. In the position shown in Fig. 1, the pin 9 is brought so that a shoulder 14 of a head 13 rests against the bottom 21 of the bore 5 by means of the compression spring 10. In this position, the pin 9 protrudes beyond the back end 4 of the bolt head 3. If the lock bolt 1 is inserted into a rotary closure cylinder, then the pin 9 is lowered by the action of the substantially stronger housing spring and the back end 23 of the pin 9 is flush with the back end 4 of the bolt head 3. With a normal actuation of the closure cylinder, the pin 9 has no function and serves merely as a locking element in the event of an unauthorised unlocking attempt. For this, please also refer to the above mentioned WO 87/05654.

An embodiment is also conceivable in which this locking pin 9 is omitted. In that case, the bore 11 in the bolt head 3, the bore 12 in the bolt tip 2, and the compression spring are omitted.

15 When the lock bolt 1 is inserted, if an associated key is inserted into the key channel of the rotor, then first the bolt tip 2 in the bolt head 3 is slid until its back end 19 rests against the bottom 21 of the bore 5. Then the bolt head 3 is slid radially outward for the insertion of the housing pin. In so doing, the housing pin rests against the back end 4 of the bolt head 3. The pin 9 is lowered in the bolt head 3 and has no function, as 20 mentioned. Consequently in the use provided, the lock bolt 1 essentially works like a conventional lock bolt. If a vibrational movement is exerted on the bolt tip 2 in an unauthorised unlocking attempt, then this movement is essentially not transmitted to the back end 4 of the bolt head 3 and is thus ineffective.

A rotary closure cylinder can have one lock bolt 1 or a number of them, preferably, though, several lock bolts 1 of a cylinder are embodied according to the invention.

p:\wpdocs\map\speci\609728. I lo

Claims

1. A lock bolt for a safety lock, the safety lock including a closure cylinder, a rotor mounted for rotation relative to the closure cylinder the rotor including a key channel, a housing pin mounted to the cylinder for movement relative to the rotor between a release position in which it permits relative rotational movement between the cylinder and the rotor and a retention position in which relative rotation between the cylinder and rotor is inhibited, and a housing spring urging the pin into the retention position, the lock bolt including a bolt head operatively mounted to the rotor when in use, and movable relative thereto, the bolt head being arranged in operative abutting relation to the housing pin so that movement thereof can move the housing pin into the release position, the lock bolt further including, a bolt tip operatively carried by the bolt head for limited movement relative thereto between extended and retracted positions, the bolt tip when in use and in the extended position extending into the key channel, spring means urging the bolt tip into the extended position the arrangement being such that at least initial movement of the bolt tip from the extended position towards the retracted position is relative to the bolt head.

2. A lock bolt according to claim 1 wherein the bolt tip is supported on the bolt head so that it can slide between the extended and retracted positions so as to enable said limited movement relative thereto.

3. The lock bolt according to claim 2, wherein the bolt head includes a longitudinal bore therein in which the bolt tip is supported so that it can slide between the extended 25 and retracted positions.

4. The lock bolt according to claim 2, wherein said longitudinal bore is a blind bore against the bottom of which the bolt tip rests or is adjacent to in the retracted position.

5. The lock bolt according to claim 3 or 4, wherein the longitudinal bore includes a lateral recess in the inner wall thereof in which a projection on the bolt tip is located p:\wpdocs\map\speci\609728. I lo so as to inhibit removal of the tip from the bore.

6. The lock bolt according to any one of claims 3 to 5, wherein said spring means is disposed within the longitudinal bore.

7. The lock bolt according to any one of claims 1 to 6, further including a locking pin operatively mounted to the bolt head, and normally protruding from the bolt head in a direction opposite to the bolt tip and can be retracted against the opposing force of a spring element in the bolt head.

8. The lock bolt according to claim 7, wherein said spring element is disposed in a longitudinal bore in the bolt tip.

9. The lock bolt according to claim 8, wherein the longitudinal bore in the bolt tip 15 is in a peg-shaped projection portion of the bolt tip. A rotary closure cylinder with at least one lock bolt according to any preceding claim. 20 11. A lock bolt substantially as hereinbefore described with reference to the drawings. DATED this 22nd day of July, 1999 ERNST KELLER By His Patent Attorney DAVIES COLLISON CAVE p:\wpdocs\map\speci\609728. 11o