AU755768B2 - A two point window lock - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT 0* 4.

*4 94 9 4* 4e *4 4 Name of Applicant: Actual Inventor: ~OOIM%~DS'GCv~z-TI- FROOUQTS PTY -Tf beeKWee() USRALAPTY~.

004 239 392) \5 R

SEFC

Paul WHYBIRD 'yrV Address for Service: 4* 4* EJ 0 CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

A TWO POINT WINDOW LOCK 404 4. 4 4.

44 Invention Title: Details of Associated Provisional Application: No. P09422 filed on 25 September 1997 The following statement is a full description of this invention, including the best method of performing it known to us: 2 This invention relates to a lock and particularly to a lock for a sliding window which can lock the window with two lock tongues.

The invention will be described with reference to double hung windows, but it should be appreciated that no limitation is meant thereby.

Double hung windows (otherwise known as vertically sliding windows) comprise a window which moves vertically relative to another window.

One type of double hung window has a fixed window and a moving window which moves vertically relative to the fixed window. Another type of double hung window has two windows which both move relative to each other.

These windows are counterbalanced by weights or springs to enable the windows to exhibit a smooth up and down motion. Such double hung windows are well known in the art.

A difficulty has arisen with locking such vertically sliding windows *in a secure manner. Traditionally, camming catches or other types of catches o *o 15 have been used, but if the window glass is broken, an intruder can manipulate 0 go the catches to open the window.

Australian patent 594577 describes a lockable catch for vertically sliding windows. This catch has a single lock tongue in the form of a flat lock plate. The catch has a main body and a pivoting handle. Depression of the 0 20 handle retracts the lock plate. The catch is fixed to the moving window and the lock plate catches against a lip on the surround frame of the fixed window. This o:o catch includes a lock barrel to allow the lock plate to be locked in the extended position. This provides a measure of security, as should an intruder break the window glass, the intruder cannot readily slide the window open.

This disadvantage with this catch is that the lock plate moves only a few millimetres between its locking and unlocking position. Sliding windows in general are formed with an aluminium or timber surround frame, and have a degree of flexibility. An intruder can insert a jemmy between the two windows, and if sufficient force is applied, the windows can be deformed sufficiently to unlock the lock plate.

The present invention is directed to a lock which can have a lock plate similar to that of Australian patent 594577, but which includes a second lock tongue to improve window security.

It is an object of the invention to provide a lock for a sliding window which may overcome the abovementioned disadvantages or provide the public with a useful or commercial choice.

In one form, the invention resides in a lock for a sliding window, the lock having a first lock tongue and a second lock tongue, the first lock tongue being operatively associated with a handle such that operation of the handle causes the first lock tongue to move between a locking and unlocking position, the second lock tongue being operable between a locking and unlocking position by an operating member which is independent of the handle.

It is preferred that one of the lock tongues locks against a horizontal portion of the window or surround or the other lock tongue locks against a vertical portion of the window or surround.

***The double locking arrangement makes the lock more secure 15 against intrusion and attempted jemmying of the window.

**In an embodiment, by having one lock tongue locking against a vertical portion of the window or surround and the other lock tongue locking against a horizontal portion of the window or surround, it becomes impossible or difficult to attempt to jemmy the window lock open.

S 20 The lock is suitable for use with sliding windows or doors and includes vertically sliding windows and horizontally sliding windows, screen .doors and the like.

The lock may have a main body portion which can support the first and the second lock tongue, as well as the handle. The main body portion can also support a key cylinder barrel to enable one or both of the locked tongues to be locked.

The main body portion can be formed from plastics, metal or other suitable materials.

The first lock tongue may comprise a substantially flat plate and therefore can be seen as a lock plate. The lock plate can slide relative to the main body between an extended locking position and a retracted unlocking position. If desired, the lock plate can be biased to a normally extended position.

The bias can be in the form of one or more biasing members such as springs.

The first lock tongue is operatively associated with the handle.

The handle may be a pivoting handle such that pivoting of the handle causes movement of the lock tongue. The first lock tongue and the handle can be directly coupled together, or can be each coupled to a pivot rod.

The second lock tongue may comprise a lock bolt. The lock bolt may be rod like in configuration. The lock bolt can move between its locking and unlocking position, and it is preferred that the lock bolt reciprocates between its locking and unlocking position.

It is preferred that the second lock tongue moves at right angles to the first lock tongue and moves substantially in the same plane or in parallel planes.

The second lock tongue may be biased to adopt a naturally extending position, and the bias may be achieved by a spring.

15 The second lock tongue is operable between its locking and unlocking position by an operating member. In one form, the operating member can comprise a lock barrel whereby operation of the lock barrel causes extension and retraction of the second lock tongue. In another form, the operating member V' comprises a snib, a lockable snib on a second handle which may also be lockable.

The first lock tongue may function as a latch or a lock. Thus, the first lock tongue can be a simple latch whereby it can be opened by operation of the handle, or can also be locked whereby a key is required to operate the first lock tongue.

The second lock tongue may bedesigned in a similar manner, but it is preferred that the second lock tongue functions only as a lock tongue and not a latch tongue.

It is preferred that the second lock tongue can be retracted to its unlocking position and kept in that position such that the first lock tongue can function as a latch or lock depending on the circumstances. Thus, for normal use, the lock can function as a conventional type latch or catch. However, should greater security be required, the second lock tongue can be operated to lock into position.

It is preferred that the first and second lock tongues can be locked in position by a single operating member, and preferably the same operating member which operates the second lock tongue (which in an embodiment, is a lock barrel). This arrangement simplifies use of the lock.

An embodiment of the invention will be described with reference to the following drawings in which: Figure 1 shows an exploded view of a lock according to an embodiment of the invention; Figure 2 shows the lock of Figure 1 with particular emphasis on how the first lock and the second lock tongue interact with each other; and Figure 3 shows an assembled version of the lock tongue of Figure 1.

~Referring initially to Figure 1, the main components of lock 10 are a 15 first lock tongue in the form of a reciprocating lock plate 11, a second lock tongue in the form of a reciprocating lock bolt 12, a pivoting handle 13, a main body S:portion 14, a rotating cam 15, and a lock barrel 16.

Main body portion 14 is formed from die cast metal, plastic or other suitable engineering material. Main body portion 14 has a block 17 with a bore 18 extending therethrough to accommodate lock barrel 16. In front of block 17 is a shouldered pin 19 which extends through opening 20 in cam 15 such that cam o :*15 can attach to and rotate about pin 19.

Lock bolt 12 is supported by guides 21a, 21b, this being more clearly shown in Figure 3. Lock bolt 12 can be reversed such that it can be supported by guide 21a (shown in Figure 3) or by guide 21b in the reverse position. This means that lock bolt 12 can be simply turned 1800 if desired.

Main body portion 14 includes longitudinal parallel slots or guides 22 to allow lock plate 11 to slide relative to main body portion 14. Lock plate 11 has a leading ramped hooked nose portion 23 (better illustrated in Figure a flat main body 24, and a rear edge formed with an inverted channel 25. Channel extends around an elongate pivot rod (not shown), the function of which will be made clearer below.

Lock plate 11 has two spaced apart slots 26, 27 in which are positioned two springs 28, 29, the springs functioning to bias lock plate 11 into its extended locking position. One end of springs 28, 29 pushes against lock plate 11 while the other end pushes against the main body portion. Lock plate 11 has a forward rather large transverse slot 30, the purpose of which will be described in greater detail below.

Handle 13 is of more or less conventional design, and is similar to the handle in Australian patent 594577. Handle 13 pivots and has a pair of lower channels 31, 32 which extend about the same pivot rod that channels 25 of lock plate 11 extend about (the pivot rod itself not being shown for reasons of clarity).

Depression of handle 13 pulls back channels 31 which in turn retracts the pivot rod (not shown) which in turn retracts lock plate 11 to its unlocking position.

Release of handle 13 causes lock plate 11 to move to its extended locking position by virtue of it being biased by springs 28 and 29. The amount of sliding movement of lock plate 11 is not great, and typically is between 5 to millimetres.

Turning now to lock bolt 12, lock bolt 12 in the embodiment is formed from a steel rod. One end of 33 of lock bolt 12 is turned and extends through opening 34a in cam 15. Lock bolt 12 is biased into a retracted position by spring 34 which sits around lock bolt 12 and behind guides 21a (or 21b if the lock bolt is reversed). This arrangement is better illustrated in Figure 3.

Cam 15 can be rotated about pin 19 via lock barrel 16. Lock barrel 16 has a lug 35 which abuts against a lug 36 on cam 15. Rotation of lug causes cam 15 to rotate about pin 19. The rotation of cam 15 causes extension and retraction of lock bolt 12 as lock bolt 12 is attached to cam 15 via opening 34a.

Lock barrel 16 can be locked in position which in turn locks lock bolt 12. Conversely, lock barrel 16 can be turned to the unlocked position such that lock bolt 12 can be moved to its retracted unlocking position.

Figure 2 shows in plan view how cam 15 functions and this figure shows more clearly how cam 15 functions to connect both lock bolt 12 and lock plate 11. Cam 15 in Figure 2 shows lug 36 abutting against lug 35 on lock barrel 16. Cam 15 has an opening 34a in which the one end 33 of lock bolt 12 can pass. Cam 15 further includes an abutment 38. Abutment 38 extends above and below the main face of cam 15 which allows cam to be reversed which is necessary should the position of lock bolt 12 need to be reversed. Abutment 38 rides against the edges of the slot 30 which is on lock plate 11. This function will now be described in greater detail.

Lock plate 11 is biased via springs 28 and 29 into the extended position. Abutment 38 in the position illustrated in Figure 2 prevents lock plate 11 from moving to its extended position it functions as a hold back). When lock barrel 16 is turned, cam 15 is turned as well which causes abutment 38 to move to the other side of slot 30. This now allows lock plate 11 to move forwardly into its extended position, the amount of movement corresponding more or less to the width of the slot 30 being about 5 to 15 millimetres, which is i sufficient to allow lock plate 11 to lock or latch into an adjacent window or surround. Rotation of the cam also causes extension or retraction of lock bolt 12.

The arrangement of spring 34 on lock bolt 12 and the springs 28 and 29 on lock plate 11 are such to "balance" the system, thereby placing less wear and tear on the lock barrel 16. For instance, lock plate 11 is biased to S•move forwardly, but this causes lock bolt 12 to compress its spring 34.

Retraction of lock plate 11 is facilitated by the pushing effect of spring 34 on cam 15. Similarly, extension of lock bolt 12 against the bias of fix spring 34 is *.oo facilitated by the pushing action of springs 28 and 29 on lock plate 11.

The arrangement allows the lock to lock a sliding window in two positions in a convenient manner. Lock barrel 16 can lock both lock plate 11 and lock bolt 12 in position.

It should be appreciated that various other changes and modifications can be made to the embodiment described without departing from the spirit and scope of the invention as claimed.

Claims (24)

1. A lock for a sliding window, the lock having a first lock tongue and a second lock tongue, handle and a main body portion which supports the handle and first and second lock tongues, the first lock tongue being operatively associated with the handle such that operation of the handle causes the first lock tongue to move between a latched and unlatched position and the second lock tongue is operable between a locking and unlocking position by an operating member which is independent of the handle and in use, the first lock tongue latches against a horizontal or vertical portion of a window or surround and the second lock tongue locks against the other of the vertical or horizontal portion of the window or surround.

2. The lock of claim 1, wherein the first and second lock tongues are connected by means of a cam and rotation of the cam can move the second lock tongue between the locked and unlocked positions and when the second lock tongue is in the unlocked position, the first o..tongue can be operated by the handle between the latched and unlatched positions.

3. The lock of claim 1 or claim 2, wherein the main body portion S 20 has opposing sides and when in the locked position, the second lock *.*tongue can project from one said side and the second tongue is able to be reversed so as to project from the other side when in the locked position.

4. The lock of any one of the preceding claims, wherein the lock is used on sliding windows or doors including vertically sliding windows and horizontally sliding windows and screen doors.

The lock of claim 4, wherein the main body portion supports a key cylinder barrel to enable one or both of the locked tongues to be locked.

6. The lock of any one of the preceding claims, wherein the first lock tongue is a substantially flat lock plate.

7. The lock of claim 6, wherein the lock plate slides relative to the S main body between an extended locking position and a retracted unlocking position.

8. The lock of claim 6 or claim 7, wherein the lock plate can be biased to a normally extended position.

9. The lock of claim 8, wherein the bias is in the form of one or more biasing members such as springs.

The lock of any one of the preceding claims wherein the handle is a pivoting handle such that pivoting of the handle causes movement of the lock tongue.

11. The lock of claim 10, wherein the first lock tongue and the handle are directly coupled together.

12. The lock of claim 10, wherein the first lock tongue and the handle are each coupled to a pivot rod.

13. The lock of any one of the preceding claims wherein the second lock tongue comprises a lock bolt. 15

14. The lock of claim 13, wherein the lock bolt has a rod like So configuration.

The lock of claim 13 or claim 14, wherein the lock bolt ~reciprocates between its locking and unlocking position.

16. The lock of any one of the preceding claims wherein the second lock tongue moves at right angles to the first lock tongue and moves substantially in the same plane or in parallel planes.

17. The lock of any one of the preceding claims wherein the second lock tongue is biased to adopt a naturally extending position.

18. The lock of any one of the preceding claims wherein the second lock tongue is operable between its locking and unlocking position by an operating member, the operating member comprising a lock barrel whereby operation of the lock barrel causes extension and retraction of the second lock tongue.

19. The lock of any one of claims 1-17, wherein the operating member comprises a snib, a lockable snib on a second handle. The lock of any one of the preceding claims wherein the first -IPlock tongue functions as a latch or a lock.

S

21. The lock of any one of the preceding claims wherein the second lock tongue functions only as a lock tongue and not a latch tongue.

22. The lock of any one of the preceding claims wherein the second lock tongue can be retracted to its unlocking position and kept in that position such that the first lock tongue can function as a latch or lock depending on the circumstances.

23. The lock of any one of the preceding claims wherein the first and second lock tongues are locked in position by a single operating member.

24. The lock of claim 23, wherein the operating member is a lock barrel. A lock substantially as hereinbefore described with reference to the drawings. Dated this 2 3 rd day of September, 2002 15 LOCKWOOD SECURITY PRODUCTS PTY LIMITED :by their Patent Attorneys CULLEN CO 0* .g.