AU2003262314B2

AU2003262314B2 - Security Lock Mechanism

Info

Publication number: AU2003262314B2
Application number: AU2003262314A
Authority: AU
Inventors: John Walsh
Original assignee: Safecorp Financial Services Pty Ltd
Current assignee: Safecorp Financial Services Pty Ltd
Priority date: 2002-11-21
Filing date: 2003-11-17
Publication date: 2005-08-18
Anticipated expiration: 2023-11-17
Also published as: AU2003262314A1

Description

P001 Section 29 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: Security Lock Mechanism The following statement is a full description of this invention, including the best method of performing it known to us: SECURITY LOCK MECHANISM The present invention relates to improvements in security lock mechanisms for closure members of cabinets or the like where the lock is remote from the opening or latching handle. Preferably such security lock mechanisms utilize multipoint (typically three point) latching and are known in Australia as a class lock.

There is an existing approved class lock structure utilizing a main latch plate located inwardly of the door and rotated by an external knob or handle. The main latch plate has a main latching tongue extending laterally from it and two auxiliary tongues each connected to oppositely extending locking bars or rods to provide the three point latching capability of the mechanism. The auxiliary tongues also include cam members that slide in guide tracks as the main latch plate is rotated such that the guide tracks move outwardly with respect to each other when the mechanism is moved to a latching position and inwardly toward each other when the mechanism is moved to a delatched position. Security locking is achieved by providing a secure type lock, remote from the main latch plate and its associated operating handle, adapted to operate a locking bar that in a first position frees the aforesaid guide tracks to move inwardly when the mechanism is being delatched, and in a second position, blocks inward movement of the guide tracks to prevent the mechanism being moved to the delatched position. The secure type lock may be any approved key operated security type lock such as a key operated BILOCK (registered trade mark), however, other types of locks might also be employed. The existing approved "C" class lock structure briefly described in the foregoing has worked satisfactorily for its purpose for many years and has the advantage that if the handle and/or the lock is drilled out in an attempt to gain unauthorized access, the mechanism remains in the latched position and it is either difficult to or impossible to delatch same.

The difficulty with latch or lock structures of this type is that the manufacturing steps required to make and assemble same are significant making the cost of producing same quite high.

The objective of the present invention is to provide an improved structure for a lock mechanism of the aforementioned type which will reduce the costs of producing and assembling same, and in certain preferred aspects, improve C performance.

0 Accordingly, the present invention provides a lock mechanism including an IND external operating handle with a drive spindle extending internally being rotatable in response to rotation of said external operating handle, an internal latch plate mounted for rotation between a latched position and a delatched position, the internal latch plate being driven remotely between said latched and said IND delatched position via cam plate means connected for rotation with said drive

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a spindle and engagable with said latch plate to rotate said latch plate in response 0 10 to rotation of said external operating handle.

Preferably, the present invention also includes locking means to lock said latch plate in said latched position, said locking means being located remote from said external operating plate. Conveniently, the locking means may include an internally located cam lock disc plate rotatable in the same plane as said internal latch plate, each of said latch plate and said cam lock disc plate having a peripheral edge region which is at least partially semicircular and convex with a concave recess formed therein, whereby, in the latched position, a convex semicircular edge region of the cam lock disc plate is located, at least partially within the concave recess in said latch plate, thereby preventing rotation of the latch plate, and in the delatched position, the concave recess of said latch plate and said cam lock disc plate are located adjacent one another whereby the latch plate is permitted to rotate.

Other preferred features and aspects of this invention may be as defined in claims 4 to 17 as annexed hereto, which claims are hereby made part of the disclosure of this specification.

The invention will now be described with reference to the accompanying drawing (Fig 1) showing one preferred embodiment of the present invention. The drawing is an exploded view of the main components forming the desired lock mechanism with the lock device being emitted for the sake of clarity. The lock device may be any suitable or approved lock device including a BILOCK (registered trade mark) device known in this art.

With reference to the annexed drawing, the lock mechanism 10 is intended to be mounted to a closure member 11 of a cabinet, container, drawer or the like 1 (not shown) intended to be secured. The lock mechanism includes an externally c located operating handle arrangement 12 with a housing 13 and a swing handle 1 14 which, in the position illustrated, is located flush with the closure member 11 IDwithin the housing 13. The operating handle arrangement 12 may include a boss member 15 which is secured via a screw member 16 such that an opening 17 in the swing handle 14 surrounds the boss member 15 in the latched position Sillustrated. The boss member 15 prevents inadvertent movement of the swing IDhandle 14 but when it is desired to operate same, the swing handle 14 is pivoted

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Soutwardly over the boss member 15 and then rotated about a rotation axis 18. If 0 10 added security is required, a ring formation 19 might be provided to the outer face of the boss member 15 through which a padlock (not shown) might be secured to prevent the swing handle 14 being swung outwardly which in turn prevents the swing handle 14 from being rotated.

The lock mechanism further includes a relatively thick metal plate (typically steel) secured to the rear of the closure member 11 and spaced therefrom. A support bush 21 is provided with an internally threaded bore 22 and an external surface formed by a flange 23 of increased diameter relative to the remainder of same 24. Adjacent to the inner end of the support bush 21 is a groove 25 adapted to receive and retain a circlip 26. The internal threaded bore 22 of the support bush 21 is threaded onto the threaded portion 27 of the operating handle arrangement 12.

Most of the lock mechanism illustrated in the drawing is located inwardly of the security plate 20 and includes a latch plate 28 with an internal bore 29 adapted to fit over and be rotatable on the smaller diameter portion 24 of the support bush 21. The latch plate 28 includes a laterally extending latch tongue and a main body portion 31 with generally semicircular edge regions 32 and 33, a rectangular recess 34, a semicircular recess 35 and two opposed bores 36 and 37 to enable remote locking bars 38 and 39 to be secured thereto via pivot pins 41 and washers 42 and E clips 43. The operating handle arrangement 12 includes a drive spindle 44 rotatable by rotation of the swing handle 14, with the drive spindle 44 having a square section onto which a drive cam 45 is fitted via the square opening 46 formed in one end. The drive cam 45 is then retained on the drive spindle 44 via a washer 46 and nut 47. The drive cam 45 includes a radially extending leg 48 with a bent tab portion 49 at its outer end, the tab portion 49 being engagable in the rectangular recess 44 in the periphery of the latch plate 28. As a result of this configuration, rotation of the swing handle 14 will rotate the drive cam 45 which in turn rotates the latch plate 28 between a latched position (illustrated) and a delatched position, provided that the latch plate 28 is permitted to rotate in this manner as discussed in the following.

If it is desired to stop the latch plate 28 being rotated to the delatched position, a separate cam lock disc plate 50 is provided mounted via an internal bore 51 on a support bush and nut 52 which in turn is secured to the locking device (not shown). The locking device may include a key operated locking device such as a BILOCK (registered trade mark) or any other suitable device, mounted through apertures 53, 54 in the closure member 11 and the security plate 20. The locking device rotates a second drive cam 55 formed similarly to the drive cam 45 and having a tab portion 56 engagable in a rectangular recess 57 in the outer edge of the cam lock disc plate 50. The cam lock disc plate also includes a semicircular concave recess 58 in its outer edge region 59 but apart from the recesses 57, 58, the outer edge region 59 is circular. Thus in a locked and latched position, a circular edge region of the cam lock disc plate 50 is positioned within the concave semicircular recess 35 of the latch plate 28 thereby preventing the latch plate 28 from being rotated via the swing handle 14. In an unlocked position, the locking device may be operated to rotate the drive cam and thereby the cam lock disc plate 50 to position the semicircular recess 58 opposite the semicircular recess 35, thereby permitting the latch plate 28 to be rotated to the delatched position or back to the latched position as may be desired. It will be appreciated that the lock mechanism can only be locked when the latch plate is in the latched position as illustrated in the annexed drawing.

It should be appreciated that variations and modifications to the above described preferred embodiment may be made within the scope and spirit of the present invention as defined in the annexed patent claims.

Claims

1. A lock mechanism including an external operating handle with a drive IN spindle extending internally being rotatable in response to rotation of said external operating handle, an internal latch plate mounted for rotation between a latched position and a delatched position, the internal latch plate being driven remotely between said latched and said delatched positions via cam plate means (Ni connected for rotation with said drive spindle and engagable with said latch plate IND to rotate said latch plate in response to rotation of said external operating handle.

2. A lock mechanism according to claim 1 further including locking means to lock said latch plate in said latched position, said locking means being located remote from said external operating plate.

3. A lock mechanism according to claim 2 wherein said locking means includes an internally located cam lock disc plate rotatable in the same plane as said internal latch plate, each of said latch plate and said cam lock disc plate having a peripheral edge region which is at least partially semicircular and convex with a concave recess formed therein, whereby, in the latched position, a convex semicircular edge region of the cam lock disc plate is located, at least partially within the concave recess in said latch plate, thereby preventing rotation of the latch plate, and in the delatched position, the concave recess of said latch plate and said cam lock disc plate are located adjacent one another whereby the latch plate is permitted to rotate.

4. A lock mechanism according to claim 3 wherein said cam lock disc plate is rotated by a lock device, at least part of which is located, in use, externally and laterally spaced from said operating handle.

5. A lock mechanism according to claim 4 wherein said lock device is key operated.

6. A lock mechanism according to any one of claims 1 to 5 wherein said cam plate means includes an L-shaped cam member having a first leg extending radially from said drive spindle including connection means to enable said cam member to rotate with said drive spindle, said cam member having at its radial outer end, a tab member bent in an axial direction to engage in a drive recess or opening in said latch plate.

7. A lock mechanism according to claim 6 wherein the drive recess is formed in a peripheral edge region of the latch plate.

8. A lock mechanism according to claim 6 or claim 7 wherein said latch plate includes an integrally formed radially extending latching tongue and opposed remote locking bars pivotally connectable to said latch plate on opposite sides of said latching tongue.

9. A lock mechanism according to claim 8 wherein said latch plate, said cam lock disc plate, said locking bars and said L-shaped cam member are fabricated from metal plate.

A lock mechanism according to any one of claims 1 to 9 wherein the operating handle includes an externally located housing and a handle member which in the latched position is located at least partially within the housing flush with a closure member to which the lock mechanism is mounted, the handle member being pivotal outwardly when being rotated to move the lock mechanism to the delatched position.

11. A lock mechanism according to claim 10 wherein said closure member includes a separate metal plate member located between the latch plate and the operating handle, the separate metal plate member at least surrounding the region of the lock mechanism and being secured to the closure member.

S12. A lock mechanism according to any one of claims 1 to 11 wherein said N latch plate is mounted on a bush member for free rotation relative to said bush member.

13. A lock mechanism according to claim 12 wherein said bush member forms part of said operating handle.

14. A lock mechanism according to claim 13 wherein said bush member is IND oreleasably secured to said operating handle.

A lock mechanism according to claim 1 including locking means to lock said latch plate in said latched position, said locking means including an internally located cam lock disc plate rotatable in the same plane as said internal latch plate, each of said latch plate and said cam lock disc plate having a peripheral edge region which is at least partially semicircular and convex with a concave recess formed therein, whereby, in the latched position, a convex semicircular edge region of the cam lock disc plate is located, at least partially within the concave recess in said latch plate thereby preventing rotation of the latch plate, and in the delatched position, the concave recess of said latch plate and said cam lock disc plate are located adjacent one another whereby the latch plate is permitted to rotate.

16. A lock mechanism according to claim 15 wherein said cam lock disc plate is rotated by a lock device, at least part of which is located, in use, externally and laterally spaced from said operating handle.

17. A lock mechanism according to claim 16 wherein said lock device is key operated.

18. A lock mechanism substantially as described herein with reference to the accompanying drawing. DATED this 17th day of November 2003 LOCK FOCUS PTY LTD WATERMARK PATENT TRADE MARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA P22151AU00 SKP/JC