IL174062A

IL174062A - Attack resistant double cylinder lock

Info

Publication number: IL174062A
Application number: IL174062A
Authority: IL
Original assignee: Mul T Lock Technologies Ltd
Priority date: 2006-03-02
Filing date: 2006-03-02
Publication date: 2011-07-31
Also published as: IL174062A0; WO2007099523A2; CN101029541A; CN101029541B; WO2007099523A3; AR059547A1

Description

174062 ,7'ji I 453523 ηικ ATTACK RESISTANT DOUBLE CYLINDER LOCK 1642MUL-IL 1 174062/2 1642mul.doc l -Mar-06 ATTACK RESISTANT DOUBLE CYLINDER LOCK FIELD OF THE INVENTION The present invention relates generally to cylinder locks and particularly to a double cylinder lock with structure resistant to forced pulling of the cylinder plug or fracture of the cylinder housing.

BACKGROUND OF THE INVENTION Double cylinder locks are well known, which may be locked and unlocked from opposite sides of a door or window. Such a lock, commonly referred to as a Euro profile cylinder, typically comprises two, separately actuable, axially aligned cylinders, each of which is connected to a cam located in a gap between the cylinders. A key may be inserted in either cylinder to throw the cam and actuate thereby a locking bolt or other locking mechanism.

A typical double cylinder assembly comprises a cylinder body adapted to be mounted transversely through a lock case and bearing a central rotatable thrower (or cam) for extending and retracting a bolt borne by the associated lock case in accordance with the sense in which the thrower is turned. At each end the body bears a cylinder mechanism comprising a rotatable plug and an array of pin, disc or other tumblers by which the respective plug is normally locked to the body.

Insertion of a proper key into either plug allows actuation of the thrower. A clutch assembly associated with the thrower ensures that the plug can be coupled rotational ly to the thrower while the other plug remains locked to the cylinder body. In an alternative form, one of the cylinder mechanisms is replaced by a plug equipped with a knob or the like which can be turned freely by hand to permit operation of the bolt from one side without a key.

Such cylinder assemblies may come under attack in an attempt to manipulate the associated lock bolt to its retracted position. Such attacks may involve the forcible extraction of the outside plug from the cylinder body, thereby providing access to turn the thrower with a suitable tool.

Alternatively an attempt may be made to fracture the cylinder body itself, e.g., at the central part which bridges its two halves. This part of the cylinder body is usually the thinnest and hence weakest, because it is relieved to accommodate the rotation of the thrower. Typically a tapped hole to receive a set screw to fix the cylinder assembly in the lock case penetrates the cylinder body at this point, still further weakening it.

European Patent 505032 describes a strengthened double cylinder lock.

If this part of the cylinder body can be fractured, then the whole of the outside half of the assembly may be extracted unless particular measures are taken in the construction of the assembly to counter this threat.

Swiss patent document CH674543 describes a double cylinder assembly in which the two cylinder plugs are connected together axially through the thrower, so that an extraction force applied to either one of the plugs can be resisted by the other. A bayonet type of connection is made between the thrower and each cylinder plug, however, which means that axial loads can be transmitted between the plugs over only part of a complete revolution. In recognition of this, additional radial screws are used to locate the plugs axially in the cylinder body, increasing the overall cost and complexity of the assembly. The bayonet connections also apply constraints on the assembly procedure, meaning in particular that the installation of the thrower must be integrated with that of the plugs.

British Patent GB2288204 describes a double cylinder lock having an axial force transmitting thrower. The double cylinder lock assembly has two key-rotatable plugs in respective ends of a cylinder body, each adapted to turn a central split thrower. The thrower is made from two interfitting arc shaped parts assembled together so as to define circumferential rims embracing external annular flanges formed on the inner ends of the plugs. The arc shaped parts are fastened together by means of a pin through aligned lug extensions. With this assembly, any axial load applied to either plug tending to extract it from the body will be transferred through the thrower to the other plug and will be resisted, irrespective of the relative angular orientation of the plugs.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved and novel double cylinder lock, as is described more in detail hereinbelow. The cylinder lock of the present invention has structure resistant to forced pulling of the cylinder plug or fracture of the cylinder housing.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which: Fig. 1 is a simplified pictorial illustration of a double cylinder lock, constructed and operative in accordance with an embodiment of the present invention; Figs. 2A and 2B are simplified pictorial illustrations of a connecting element for the cylinder lock of Fig. 1 , constructed and operative in accordance with an embodiment of the present invention; Fig. 3 is a simplified pictorial illustration of a central rotatable thrower used in the cylinder lock of Fig. 1 , constructed and operative in accordance with an embodiment of the present invention;' and Fig. 4 is a simplified illustration of the connecting element of Figs. 2A-2B assembled with the central rotatable thrower and the cylinder lock housings.

DETAILED DESCRIPTION OF EMBODIMENTS Reference is now made to Fig. 1 , which illustrates a cylinder lock 10, constructed and operative in accordance with an embodiment of the present invention.

Lock 10 may include a first cylinder housing 12 in which a first pin tumbler (or plug) 14 is rotatably disposed. Lock 10 may also include a second cylinder housing 16 in which a second pin tumbler (or plug) 17 (shown simplified in broken lines) is rotatably disposed. Each pin tumbler may be rotated by insertion of a suitable key 18 in a key way 20. Alternatively, instead of key-operated pin tumblers, rotors actuable by a turn-knob may be employed. The term "rotor" is used throughout the specification and claims to denote pin tumblers, knob-actuable rotors and any other suitable rotatable element.

Each pin tumbler may be coupled to a central rotatable thrower or cam 22 (also shown in Fig. 3). As is well known in the art, a clutch assembly (not shown) associated with the thrower 22 ensures that the pin tumbler can be coupled rotationally to the thrower while the other pin tumbler is disengaged from the thrower 22.

Reference is now-made additionally to Figs. 2A, 2B and 4. In accordance with an embodiment of the present invention, a connecting element 24 may connect first and second cylinder housings 12 and 16 together so as to transfer an axial pulling force applied to one of the cylinder housings to the other cylinder housing. Connector element 24 may be constructed of a partial cylinder with rims 26 that are received in grooves 28 (Fig. 4) formed in first and second cylinder housings 12 and 16. Connector element 24 is adapted to overlay an outer contour of thrower 22. In the non-limiting illustrated embodiment, the outer contour of thrower 22 has a recessed portion 30 (Fig. 3) with a smaller diameter than the rest of the outer contour of thrower 22. The recessed portion 30 extends between abutments 32 (Fig. 3). The connector element 24 may be shaped such that its partial cylindrical shape corresponds to the arcuate spacing between abutments 32, wherein the connector element 24 has terminal edges 34 that rest against abutments 32. In this manner, connector element 24 may be flush with the outer contour of thrower 22. Since the connector element 24 sits in the recessed portion 30 between the abutments 32, the connector element 24 rotates together with thrower 22. The rims slide freely in grooves 28 as the connector element 24 rotates. It is noted that the first and second cylinder housings 12 and 16 may have smaller diameters in the vicinity of connector element 24 so that connector element 24 can be flush with thrower 22.

As seen in Fig. 4, an axial force applied to plug 14 tending to extract it from first cylinder housing 12 in the direction of arrow 36 (or similarly an axial force applied to the other plug tending to extract it from second cylinder housing 16) will be transferred via connector element 24 to the second cylinder housing 16, thus defeating an attempt to forcefully pull out the plug or fracture the cylinder housing.

It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the features described hereinabove as well as modifications and variations thereof which would occur to a person of skill in the art upon reading the foregoing description and which are not in the prior art.

Claims

Λ 5 174062/4 jC L A I Μ S What is claimed is:

1. A double cylinder lock, comprising: a first cylinder housing in which a first plug is rotatably disposed; a second cylinder housing in which a second plug is rotatably disposed, each pin tumbler being coupled to a central rotatable thrower ; characterized by a connecting element connecting said first and second cylinder housings together so as to transfer an axial pulling force applied to one of the cylinder housings to the other cylinder housing, said connector element being adapted to overlay an outer contour of said thrower, wherein an outer contour of said thrower has a recessed portion extending between abutments and said connector element is shaped to fit between said abutments.

2. The double cylinder lock according to claim 1, wherein said connector element comprises rims that are received in grooves formed in said first and second cylinder housings.

3. The double cylinder lock according to claim 1, wherein said connector element is flush with an outer contour of said thrower.

4. The double cylinder lock according to claim 1, wherein said connector element rotates together with said thrower.

5. The double cylinder lock according to claim 2, wherein said connector element rotates together with said thrower and said rims slide in said grooves as said connector element rotates.

6. The double cylinder lock according to any one of the preceding claims and substantially as shown and described hereinabove. For the Applicant, rip 7js* David Klein, Patent Attorney Dekel Patent Ltd.