WO1997016616A1

WO1997016616A1 - Lock or latch mechanism

Info

Publication number: WO1997016616A1
Application number: PCT/AU1996/000657
Authority: WO
Inventors: Kum Weng Hui
Original assignee: Award Industries Pty. Ltd.
Priority date: 1995-10-31
Filing date: 1996-10-18
Publication date: 1997-05-09
Also published as: AUPN630295A0

Abstract

The invention consists of a latch member (4) which is adapted to be inserted into a frame member of a security grille or a door or window, which is biased to an unlocked position, preferably by a spring means (28). To move the latch member to the locked position requires a tension force to be applied to tension means such as a cable (16) or a chain which will move that latch member to the locked position and only keep the latch member in the locked position if the tension is maintained on the tensioning means. The tension is maintained by a trigger mechanism (50), which can be triggered with relatively little force at an appropriate time or emergency.

Description

LOCK OR LATCH MECHANISM FIELD OF THE INVENΗON

The present invention relates to locking mechanisms for doors, windows, security grilles, lids, covers, hatches and the like. BACKGROUND OF THE INVENTION

In many locations around the world, the need for security and protection is paramount. In such locations one form of protection is a security grille system on doors, windows and other building openings. The difficulty with an unopenable security grille is that whilst they keep intruders out, they have the effect of locking in people, particularly in a time of crisis. Attempts have been made to solve this problem but to date the solutions have been ineffective. The need to make a security grille openable is relatively straight forward, however it is the prior art mechanism's attempt to releasably lock the security grille into place which have not been successful. This has led to a resistance in the market place for such a lockable security grille system. The effects of the environment over a long period of time renders the prior art systems useless when it comes time to release the security grille in an emergency.

Another failing of the prior art system is that the latch can be a weak point, making the security grille easily opened by determined intruders.

SUMMARY OF THE INVENTION The invention provides a locking mechanism to releasably lock or secure a moveable member relative to a stationary member, said locking mechanism including a latch member adapted to be positioned in one of said members and slidable relative thereto, said latch member being able to engage the other of said members, said latch member being biased to an unlocked position and being further characterised so that when in use the application of tension and the maintenance of said tension to a tension means, interacts with said latch member, so as to move said latch member against said bias to a locked position.

Preferably said tension means is of the flexible type, such as a cable or chain.

Preferably said locking mechanism is further characterised by said tension means, which has one end attached to said latch member and cooperates with a pin or pulley means attached to a relatively stationary member to allow a remote end of said tension means to proceed in a desired direction.

Preferably said tensioning means includes a latch end which is connected to said latch member or a part of a structure connected to said latch member and a remote end away from said latch end, such that when said tensioning means is tensioned by force applied to said remote end, forces will be transferred to said latch end and thereby said latch member or said part can counter said bias, to move said latch member to a locked position.

Preferably said tension member passes through an opening in said latch member or a part of a structure connected to said latch member to said remote end. Preferably the moveable member is a door, window, lid, cover, hatch or the like.

Preferably the moveable member is a moveable or openable security grille.

Preferably the stationary member is a frame adapted to be secured to a wall or other stationary means.

Preferably the stationary member is a window frame or door frame. Preferably a tripping mechanism is used to release said tension means when required.

Preferably said remote end of said tension means includes a means to provide mechanical advantage for an operator.

Preferably the latch and all moving parts are made from non-corrosive material.

The advantages which result from the above features, include that an operator, by means of very little force, is able to open a security grille in time of emergency. They provide an advantage such that should the tension means break, the security grille is opened automatically. By the moving parts, such as the springs and the latch being made of a non-corrosive material (such as stainless steel) corrosion which would normally tend to seize lock mechanisms, will have little effect on the operation of the improved mechanism when it is required to be used. The use of mechanical advantage at a remote location, allows an operator, whether child or infϊrmed adult, to operate the disengagement of the latch in order to open the security grille.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings in which: Figure 1 is a plan view through a latch mechanism of the present invention;

Figure 2 is a cross section of the apparatus of figure 1 ;

Figure 3 is an end view of the apparatus of the latch mechanism of figure 2;

Figure 4 is a front end view of the apparatus of figure 2; Figure 5 is a cross section of a modified version of the apparatus of figure 1 , in piece of square hollow section frame;

Figure 6 is a perspective view of a triggering mechanism which can be used with the apparatus of figures i and 2;

Figure 7 is a plan view of a latch mechanism of an alternative to figures 1 to 5; Figure 8 illustrates a cross section through the apparatus of figure 7;

Figure 9 is an end view of the apparatus of the latch mechanism of figure 8;

Figure 10 is a front end view of the apparatus of figure 8;

Figure 11 is an alternative hydraulic latch mechanism to that of figures 1 to 5 and 7 to 10; Figure 12 is an alternative hydraulic mechanism to the latch mechanisms of figures 1 to

5 and 7 to 11;

Figures 13 to 16 illustrate adaptations of the apparatus of figures 1 to 12 for use with sliding doors and windows;

Figures 17 to 21 illustrate other embodiments of locking mechanisms which are alternatives to figures 1 to 16;

Figure 22 is a side elevation of the workings a trigger mechanism of an alternative to figure 6 in an unlocked position;

Figure 23 is a side elevation showing the apparatus of figure 22 in a locked position;

Figure 24 is a front elevation of the apparatus of figure 22; Figure 25 is a plan view of an alternate trigger mechanism;

Figure 26 is a plan view of the apparatus of Fig 25 with the trigger in the locked position;

Figure 27 is a section through line XX of figure 26; Figure 28 illustrates another latch and sliding mechanism to that of the previous figures;

Figure 29 illustrates a cross section through another latch mechanism which utilises a tension spring;

Fig 30 illustrates a cross section through latch arrangement of fig 29, with the cable moving at 90° to the latch member movement;

Fig 31 illustrates a plan view of the apparatus of both figs 29 and 30with part of the cable removed;

Fig 31 A illustrates a front elevation of the apparatus of fi? 1. with the cable remnvpH;

Fig 32 illustrates a front elevation of a security grille for use with the present invention; Fig 32A illustrates the apparatus of fig 32 but with those parts which are movable relative to stationary parts being indicated by shading;

Fig 33 illustrates a hinge construction for use with the apparatus of fig 32;

Fig 34 illustrates a lock mechanism of fig 30 in cross section, installed in the apparatus of fig 32; Fig 35 illustrates a lock mechanism similar to fig 1 in cross section, installed in the apparatus of fig 32;

Fig 36 illustrates a perspective view of the security grille of fig 32 in an open position;

Fig 37 illustrates a side elevation of the apparatus of fig 36;

Fig 38 illustrates a front elevation of double doors which may utilise a latch mechanism of figures 13,14,15 or 16; and

Fig 39 illustrates a front elevation of a door with dead lock utilising a latch mechanism of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Illustrated in figure 1 , is a latch mechanism 2 which includes a latch bolt 4 and a shaft 6 which is connected to latch bolt 4 by means of a pin 8.

The shaft 6 has a yoke portion 10 on its other end. The yoke portion 10 includes a recess 12 in which is located a pin 14 which is part of a frame of a fitting (not illustrated in this figure) in which the latch mechanism 2 sits and moves relative thereto. The frame (not illustrated) may be a part of a security grille, a door, a window, a door or window frame. The pin 14 (which can be or include a pulley, if friction is to be reduced) has a radius greater than the minimum bend radius of a cable 16. The pin 14 is securely or rigidly mounted to a frame or other component on, in or to which the yoke portion 10 will be located, so that the latch bolt 4 is able to move relative to said pin 14 and said frame or component. The cable 16 runs around the pin 14. The cable 16 has a swaged or other formed teralini 18. The termini 18 engages surface 20 at the rear of the yoke portion 10. This arrangement allows a portion of the cable 16 to move relative to an inside portion of the yolk portion 10 of shaft 6 when the cable is tensioned in a direction which is not the locking direction of the latch bolt 4 and produces movement of the latch bolt 5 in a locking direction. The cable 16 passes through a hole 22 in the yoke portion 10, and around the pin 14, and back through another hole 24 in the yoke portion 10. The cable 16 then proceeds, via friction reducers such as pulleys, bearing surfaces and die like, around corners to a remote location (see Fig 6) where the cable 16 terminates in a trigger mechanism (such as trigger 50 of figs 22 to 24), which will maintain and apply tension or release the tension in the cable 16, when desired. Between the yoke portion 10 and the latch bolt 4 is a slide member 26 which, like pin 14, is attached to the frame (not illustrated) in which the latch mechanism 2 is positioned. The slide member 26 can be manufactured with a groove 27 as is illustrated in figure 1 or 2. The groove 27 receives a grub screw or other locking screw which passes through the frame to hold the sliding member in position. Alternatively the groove 27 can be used to receive a plug weld or a projection to interconnect or position the sliding member 26 relative to the frame. The shaft 6 slides in the slide member 26 and compresses a compression spring 28, which is located around the shaft 6. The compression spring 28 is compressed between the face 30 of the yoke portion 10 and the slide member 26. When the cable 16 is tensioned the latch bolt 6 engages an aperture in a fitting adjacent to another fitting so as to lock the two fittings together. The latch mechanism 2 can be mounted in either a movable or stationary fitting.

As can be seen from figures 3 and 4 the latch bolt 4 and the yoke portion 10 are of square construction, and fit into a square hollow section member (circular hollow section for round yokes) which makes up part of a frame (not illustrated). Generally speaking the yoke portion 10 and other moving parts of said latch mechanism 2 is of a shape and dimension corresponding to the frame or component, on, in or to which it is to be located. The frame can be stationary or movable. If it is stationary it can be either a supporting member or it is a housing which fits into a supporting member (as is illustrated in figure 5). The frame, if it is a supporting member, is positioned around and adjacent to an opening such as a window or doorway. The control cable 16 will pass through the wall to which the stationary frame is attached. For security reasons it may be best for the cable 16 to not be accessible by intruders. Thus for a security grille it could pass through a wall behind one of the mounting points for a security grille frame to prevent intruders accessing the cable 16. A trigger mechanism (such as trigger mechanism 50 of fig 22) for the quick release of the cable 16 is preferably provided, to thereby unlock the security grille. The trigger mechanism can be of any type providing it is triggered by means of a relatively little force. Such a type is one incoφorating an over-centred spring held lever with spring assisted release, as is illustrated in

end 40 and thus lock several locations at the same time. The leverage can be modified by means of providing a longer handle 80 to require less force to operate. The offset distance of the pin 51 to the pivots around which the spring 83 is positioned can also be varied to provide more or less mechanical advantage. Another feature that can be adjusted is the amount of offset 81 that the handle comes to rest at, which will determine how much force will be required to release the trigger mechanism 50. Springs 83 can also be included in the trigger mechanism 50 of figures 22 to 24 to assist in release. The pin 51 rotates as the lever 80 is rotated. This will prevent the cables 16 winding around the pin 51. It would be expected that the size of the release force is that able to be applied by child or infirmed elderly adult.

Preferably the trigger mechanism 50 operates by means of hydraulic or mechanical forces. Any electrical triggering devices may activate if there is a power failure or the like which will defeat the security purpose of a grille or door or window locking mechanism. Alternatively, the trigger may not activate if power is off in the case of an emergency.

Illustrated in figure 5 is an apparatus similar to figure 1. Like parts have been numbered with like numbers. The latch mechanism 2 is housed in a housing 33 and the slide member 26 is replaced by flange 32 and opening 34. Flange 32 and opening 34 serve the same purpose as slide member 26. Unlike the previous embodiment, which can be housed directly into a frame member on a security grille, the embodiment of figure 5 is first housed in a housing 33 and the housing 33 is then installed inside a similarly shaped frame member38 which makes up part of a security grille frame. As is illustrated in figure 5, the housing 33 sits in a hollow section frame member 38. The pin 14 is a part of the housing 33 unlike the apparatus of figure 1. The housing 33 can be secured to the frame member 38 by any conventional means. The latch bolt 4 is connected to shaft 6 and to a yoke portion 10 at the end of shaft 6. If desired the latch bolt 4 can be connected to the shaft 6 by any means. For example the shaft 6 can be threaded and the rear of the latch bolt 4 can have a mating female thread as is illustrated in figure 5, or they can be joined by a pin as in figure 1 and 2. A join between the shaft 6 and the latch bolt 4 is used so that the respective parts can be assembled in a housing 33.

The latch bolt 4 and yoke portion 10 can be sized to suit any size housing 33 and frame member 38. This makes the latch mechanism 2 adaptable to other openings such as windows and doors and the like.

Illustrated in figure 6 is a triggering mechanism which is adapted to catch the termini 40 of cable 16 and release the termini 40 when required. The gripping of the termini 40 can be by any known means such as spring loaded jaws (not illustrated) or other means.

A trigger 42, projecting out of the housing 44, is of the hair trigger type so that only small amounts of force need be applied before the termini 40 is released.

Preferably the housing 44 is mounted on the floor by means of screws (not illustrated) through the flanges 46. By being mounted on a floor, the trigger 42 can be easily kicked or collided with so that opening of the security grille is made easy.

Alternatively the housing 44 can be mounted anywhere that is considered appropriate by the operator or purchaser.

A series of conduits 48 deliver the cable 16 to the housing 44 of the trigger mechanism 50. Preferably the conduit 48 is chosen either is of a self lubricating type polymer to allow easy movement of cable 16 over its surfaces. Alternatively other friction reducing mechanisms or guides, such as pulleys, curved metal inserts, plastic or metal ferrules, can be used at corners 52 which are locations at which friction is greatest.

The compression or compression spring rate of the spring 28 of figs 5 and 1, is selected so that it will retract the latch bolt 4 whenever the cable termini 40 is released. In order to prevent the effects of corrosion, the relatively moving parts (for example cable 16, latch bolt 4, pin 14, spring 28 and the like) are preferably made of stainless steel, brass, galvanised steel or any other non corrosive structural material. Alternatively, if regular grade steel is used preferably the frame member 38 is positioned so that the latch closes in an upward direction. In this way, at regular intervals, oil and other lubricants can be placed over and around the latch bolt 4 so that the oil can proceed, by gravity, down through the frame 38 to lubricate all moving parts. Alternatively non-deteriorating grease can be utilised to keep the members well lubricated.

Illustrated in figures 7, 8, 9 and 10 is an alternative latch mechanism to that of figures 1 to 4. Like in figures 1 to 4, the components of the latch mechanism 2 are housed in a housing 33. The square form of latch bolt 4 of figure 7 is replaced by a round latch bolt 4. The latch bolt 4, the shaft 6 and the yoke portion 10 are all integrally formed, by either casting, moulding, forging or any other appropriate fabrication method. In this version a tension spring 52 is added as an extra safety feature. The tension spring 52 whilst adding additional force to operate the iau-h uiccii-uii-iii- 2 is. a saf ty foatu-e iu case ither of tl-e -.p-i-ϊg-. ere lo biea , one -.priiig 52 or 28 would remain operable. This may make the tension to be applied to the cable 16 greater. To activate the latch bolt 4 this greater force can be overcome by extra mechanical advantage associated with the trigger mechanism housing 50. The sliding member 26 can either be end welded by a fillet weld 49 or by a plug weld 47 This will keep the sliding member 26 in position at the end of the housing 33. Illustrated in figure 11 is a hydraulically operated latch mechanism 2. It comprises a latch bolt 4, flange 32, hole 34, shaft 6 and spring 28. Instead of yoke portion 10 a hydraulic mechanism 54 activates the latch bolt 4. The hydraulic mechanism 54 is activated by a cable 16 which attaches to a rod 63 which is a part of the sliding member 56. This cable 16 retracts a sliding member 56 which is sealed relative to shaft 6 by sliding seals 58 and sealed relative to the base 62 by sliding seals 58A. This movement builds up pressure by means of a volume change of hydraulic fluid which is located in the cavity 60. The cavity 60 is formed in the base 62 of hydraulic mechanism 54. The base 62 is secured to housing or housing 33 by a screw 64.

When pressure in cavity 60 builds up sufficiently, the shaft 6 which is free to move, is pushed to the left to engage the security grille or other member to be secured by means of latch bolt 4. When it is desired to release the latch bolt 4, the cable 16 is released from its securing mechanism by a trigger which reduces the hydraulic pressure on the fluid in cavity 60 and the spring 28 will force the latch bolt 4 to be retracted.

A simpler hydraulic operated latch mechanism 2 is illustrated in figure 12. In this embodiment activation is done by a hydraulic fluid in conduit 66, which when pressurised forces piston 68 to activate latch bolt 4. To release, the hydraulic pressure is removed by the opening of a valve and a spring 28 retracts the latch bolt 4. Illustrated in figures 13 to 16 are variations of the previous embodiments adapted for sliding windows and doors.

In figure 13 is a door stile 70 or window stile 70 which is prevented from sliding by a detent member 72, which rotates into a locking position when the latch bolt 4 moves to the right in response to cable 16 moving to the left. The member 72 pivots with respect to the latch bolt 4 to move into and out of a locking position.

Illustrated in figure 14 is an alternative to figure 13. In this embodiment the latch bolt 4 slidingly engages a lock button 74 which is spring mounted and moves to a lock position as illustrated. When the latch bolt 4 moves to the left the button 74 retracts from the panel 76 to unlock it.

Figures 15 and 16 illustrate alternative detents 78 and 80 with spring 82 for use with a system similar to figure 13.

Illustrated in figures 17 to 21 are alternative arrangements for locking mechanisms which operate in a manner similar to that of the previous embodiments. When force is exerted on the tension means, in these figures represented by the arrow head pointing to the right side of the page. Whilst these will work is a similar manner to those described above, the embodiments described previously tend to be more robust, easily adaptable to small cross sectional area frames 38 and housings 33 and generally offer more reliable and better operation.

The embodiments of figures 17, and 18 are similar and work on the principle of a wheel or gear 300 being rotatably attached to a frame or component in, on or to which the latch mechanisms 301 and 302 are positioned. The wheel or gear 300 is rotatably mounted on stationary pin 299 attached to the frame or component, so that when the L-shaped member 303 is pulled to the left in the direction of arrow 305, the member 303 drives the wheel or gear 300. This wheel or gear 300 in turn drives the L-shaped member 304 in the direction of arrow 306 to push the latch bolt 308 against the bias produced by compression spring 307, so as to move to a locked position. Sufficient relaxation of the force in the direction of arrow 305 will cause the latch bolt 308 to move, under the influence of the bias of spring 307, in the direction of arrow 309. This will in turn force member 304 in the same direction as arrow 309, but this time it will drive the wheel or gear 300, thereby moving member 303 in the direction of arrow 306. Illustrated in figure 19 the latch mechanism 310 includes a wheel 312 rotatably mounted on pin 31 1 which is attached to the frame or component in the same way as pin 299 of figs 17 and 18. The wheel 312 has a cable 313 attached to and around it at point 314. Near to point 314 a push rod 315 is attached to the wheel 312 at point 316. The push rod 315 connected to the latch bolt4 by means of pin 317. By tensing cable 313 in the direction of arrow 305 the push rod 315 will push the latch bolt 308 against the bias of compression spring 307, as in the previously described embodiments. When the force is reduced or removed in the direction of arrow 305 , the compression spring 307 forces the latch bolt back in the direction of arrow 305 back to the unlocked position.

The latch mechanism 320 of figure 20 is similar to that of figure 19 and like parts have been like numbered to that of figure 19. The latch mechanism 320 works in a similar manner to that * *βr»r - Λ»ι e »*-« « r '-IO 1

which is attached at point 322 to wheel 312. The spring 321 will function fully in the same manner and serve the same purpose as spring 307.

Illustrated in figure 21 is a latch mechanism 325 which has a latch bolt 308 and compression spring 307 the same as the embodiments of figures 17 to 19. However, in this embodiment, a lever 326 is pivoted by pin 327 to the frame 38 like similar components of the previous embodiments. A cable 313 which is attached to the lever 326 at one end, will rotate the other end of the lever 326 in an opposite direction when a force is applied to the cable 313 in the direction of arrow 305. Providing the lever 326 does not proceed past a certain point of rotation, it will move in the reverse direction under the influence of the bias of compression spring 307, when the force in the direction of aπow 305 is relaxed or removed. Illustrated in figures 25, 26 and 27 is an altemative trigger mechanism 100. Trigger mechanism 100 is enclosed in a rectangular open box type structure 102, on which can be placed a lid such as a power point cover or other plastics component, with a readily accessible and removable handle. The trigger mechanism 100 includes a base plate 104 which has in it an elongated tubular formation 108. The tubular formation 108 has a first shoulder portion 1 10 at one end of the formation 108 and a second shoulder portion 112 intermediate the ends of formation 108. The tubular formation 108 includes a bore 109 through it. In the bore 109 is positioned one limb of an L-shaped locking tube 106, which can rotate and slide in said bore 109.

The distance from shoulder 112 to shoulder 110 is of a magnitude so that when the locking tube 106 is at shoulder 110, the cable 16 is tensed. Wherein as when the locking tube 106 is resting against shoulder 112 the cable is either released of its tension or altematively the tension is released sufficiently that the latch of bolt 4 previous figures will move from a locked to an unlocked position. The base plate 104 is secured to a wall or similar structure, on the inside of a room at a remote location, by means of six countersunk screws or bolts 114.

The direction of travel of the lock tube 106 is in the directions of arrows 116 and 1 18, each of which is parallel to the direction of tubular formation 108. If the lock tube 106 is moved in the direction of arrow 116, from shoulder 112 to shoulder 110, tension is applied to the cable which in turn moves the latch from an unlocked to a locked position. When the lock tube 106 moves from the shoulder 110 to shoulder 112, in the direction of arrow 118, the tension or force in the cable 16 is released or decreased enough to move the latch bolt from the locked to m . , — I - -.1.- J — -.:*: „-,

Illustrated in figure 26 is a section through the tubular formation 108 when the lock tube 106 is in the locked position as illustrated in figure 27, in which position a latch bolt 4 of previous figures will be in a locked position. The outside diameter of the cable 16 is permanently connected to the intemal portions of lock tube 106 by means of a swaging process. This swaging process can be applied at one or more points along the length of the lock tube 106 such as for example point 120.

When it is desired to activate the trigger to unlock the latch, that is to move the latch from a locked to an unlocked position, the top end 122 of the handle portion 124 of lock tube 106 is moved in the direction of arrow 126 so that it no longer engages the shoulder 110. Because of the tension in the cable 16 and the resisting force of the bias or springs that tends to move the latch bolt 4 to an unlocked position, the handle 124 will move until such time as it engages the shoulder 112. When this has occuπed the latch bolt will have moved from the locked to the unlocked position.

An advantage of the trigger mechanism illustrated in figures 25 to 27 is that handle portion 124 can be made to any desirable length so as to be easily actuated by feet or by hand. Another means of actuating the trigger is to use a cable link (not illustrated) between the end of the handle 124 and the cover (not illustrated) of box 102, so that as soon as the cover is pulled off the box 102, the cable link will force the handle 124 to rotate in the direction of aπow 126, in which case the latch bolt 4 will move from the locked to the unlocked position.

Illustrated in Figure 28 is a latching mechanism 130 similar to those illustrated in previous figures. The latch mechanism 130 includes a cylindrical or square latch bolt 134 which is connected to hollow square or round shaft 136. Hollow square or round shaft 136 has a bore

135 through its entire length. The hollow shaft 136 can be attached to the latch bolt 134 by any known means such as a pin, brazing, screw fitting etc. The shaft 136 terminates in an end 138 having a square or annular shoulder 140. The shaft 136 passes through an end 142 of a spring housing 144 which has a spring 146 positioned therein and around the shaft 136.

End 138 is securely attached to the shaft 136 by either a screw connection, welding or other positive securing means. The end of the shaft 136 provides a shoulder for an engagement member 148 which interacts with an end member 148 swaged onto the termini 150 of the cable 16. Cable 16 cooperates by means of termini 150 and end member 148 with the end 138 which makes connection with latch bolt 134.

The hollow shaft 136 includes an opening or cut away portion 152, across which sits a cylindrical cable pin 154 (which may include pulley or other function reducing means) secured to the intemal walls of frame 156. The length of cut away portion 152 is such that there is sufficient room for shaft 136 to move relative to the pin 154 so that the latch bolt 134 can move from a locked to the unlocked position which is illustrated in Figure 28.

The spring housing 144 is secured to the frame 156 by means of a plug weld 158 through two holes previously formed in the frame 156 adjacent to the spring housing 144. The end 142 is securely attached to the spring housing 144 by means of welding or other attachment processes so that as the cable 16 is tensioned in the direction of arrow 160, this tensioning will force the termini 150 and end member 148 of cable 16 in the direction of aπow 162. This in turn forces the end 138 in the same direction and so forces the latch bolt 134 in the same direction, which moves it from its unlocked position in Figure 28 to a locked position engaging an aperture in another member to prevent the relative movement of one member relative to the other.

As the end 138 moves in the direction of aπow 162 the compression spring 146 (biasing the latch bolt 134 to the open position) becomes compressed, the maximum travel of the latch bolt 134 will be dictated by the length of cut away portion 152. The maximum travel will be limited because the shaft 136 can only move (in either direction) until such time as shoulder 164 and shoulder 166 engages the cable pin 154.

The cable 16 must have sufficient tension applied to it so as to overcome the bias of spring 146. However once the latch bolt 134 is in a locking position the tension to keep the latch bolt 134 in that locked position must be maintained. This is done by means of the various trigger mechanisms which have been described previously. By keeping the tension applied to the cable 16 the spring 146 can readily retract the latch bolt 134 from the locked to the unlocked position, as soon as the trigger is activated, so as to either fully or partially release the tension applied to the cable 16.

The embodiment of Figure 28 is particularly useful in situations where the longitudinal cavity of a door grill or window which would have a frame 156 at right angles to it (or at other angles to the direction of another frame member 164) and leads away from the cable pin 154. Illustrated in Figure 28 the frame 164 is shown at right angles but any direction in the plane of the page and within the 180° of the direction of the shaft 136 will allow for the proper operation of the anangement of Figure 28.

The shoulder 166 of shaft 136 may include a semi-circular cut-out (not illustrated) so that the cable 16 when the shoulder 166 rests against the cable pin 154, will not be damaged or clamped between shoulder 166 and cable pin 154.

The anangement of cable 16, cable pin 154, and cut away portion 152 allows a portion of the cable 136 to move relative to an inside portion of shaft 136, by travelling across shaft 136 when it exits said shaft 136, by cable 16 being tensioned in a direction which is the locking direction of latch bolt 134, and produces movement of the latch bolt 134 in a locking direction.

Illustrated in Figure 29 is a schematic version of another latch mechanism 200. In the arrangement of Figure 28, the latch mechanism 200 includes a pin 202 which is attached to a frame (not illustrated) in which is positioned latch mechanism 200. Cable 16 wraps around pin 202 starting from a termini 204 which engages a moveable member 206 with the other end of the cable 16 (after it has wrapped around pin 202) preceding in the direction of aπow 208 (and via any roundabout directions) to a trigger mechanism 50 of previous figures.

Connected to the pin 202 and thus the frame in which the latch mechanism 200 is positioned, is one end 210 of a tension spring 212. The other end 214 of tension spring 212 is connected via a pin 216 to the moveable member 206. As the remote end of cable 16 is tensioned in the direction of aπow 208, the moveable member 206 will move in the direction of aπow 218, thus extending the tension spring 212. The moveable member 206 may have directly connected to it (or via a shaft mechanism as described in previous embodiments) a latch bolt for locking and unlocking a moveable fitting relative to a stationary fitting. The frame which is not illustrated could be mounted in either the moveable or stationary fitting such as a door and door jamb. The spring tension increases as spring 212 extends, but die maximum extension of the spring 212 can only be the distance 220 from a shoulder 222 to the pin 202 from the stationary position. Once the shoulder 222 engages pin 202 the moveable member can move no further in the direction of 218 in that position. In this position the latch bolt should be in a locked position. By releasing the remote end of cable 16, the moveable member will retract under the force of the spring 212 in the direction of arrow 208, to the fully retracted position as illustrated in Figure 28. Illustrated in fig 30 is an embodiment of a latch mechanism 201, which is similar to that of fig 29. Like parts have been liked numbered. The latch mechanism 201 operates in the same manner as that of fig 29. This embodiment illustrates how the cable 16 can be made to be led away in a direction at 90° degrees to the direction of travel of the moveable member 206. This c-*π bs ?.dv--πt?.^rr-? ^,..s

above, with the embodiment of fig 29 and 30 only one configuration of components is required to achieve differing arrangements and direction that the cable 16 will adopt as it leaves the latch mechanism toward its remote end.

Because of the pin 202, the cable 16 can be led away at angles other than just 90°. In many applications, because frame members and the like are assembled at right angles to each other, a 90° anangement of figure 30 will be appropriate. But if an angle of other than 180 Degrees or 90 degrees becomes necessary, then the embodiment of figs 29 and 30 will be able to accommodate any angular requirements.

In the latch mechanism 200 and 201 of fig 29, and 30 respectively, the moveable member is made up of a U- or C-shaped integrally formed latch bolt 230, whereby the U- or C- shape is formed from a base portion 232 and two side portions 234 and 236 at 90° to base portion 232.

The two side portions 234 and 236 extend up, in figures 29 and 30, from the base portion 232 to form a bight 238, which is better illustrated in figure 31.

If desired, the moveable member 206 can be formed as a square or round hollow section.

However, when the bight 238 is present, it allows the latch mechanisms 200 and 201 of figs 29 and 30, to be used in relation with a door 242 of fig 39 to cooperate with the deadlock 240 mounted on the door 242.

Illustrated in fig 39 is a latch mechanism 200 (from fig 29), mounted in a door jamb 244. A trigger mechanism 50 is located on a side of door 242, and mounted adjacent to and on a wall 246. Cable 16 links trigger mechanism 50 to the latch mechanism 200. In use the moveable member 206 (see fig 29) is moved to a locked position such that the portions 234 and 236 extend from base portion 232 towards the dead lock 240. In this way, into bight 238 a bolt (not illustrated) from the deadlock 240 can be received. Together with a groove or aperture 241 in the door jamb 240, either of portions 234 or 236 will form a wall across the aperture 241 to prevent a bolt of the deadlock 240 from exiting the aperture 241 in the door jamb 240.

When it is required to make the door 242 open, without unlocking the deadlock 240, such as in a case of emergency, the trigger 50 is actuated, thereby moving the moveable member 206 and portions 234 and 236 in the downward direction. Because the door jamb 244 has 241 in it, this will allow the bolt (not illustrated) of dead lock 240, to pass through the 241 in the door jamb 240, which was previously closed off by one of the portions 234 or 236.

In figure 31 and 31 A, the components of figs 29 and 30 are illustrated in plan view and front elevation respectively. Hgure όi illustrates how the pin -iU-- extends between the opposing sides of frame 38, while the pin 216 extends between the opposed portion 234 and 236 of the moveable member 206 as illustrated in figs 31 and 31 A.

If desired moveable member 206 and the base 232 and portions 234 and 236 can be used as a latch bolt in the same way as latch bolt 4 of previous figures, and this is illustrated in fig 34.

Illustrated in figure 32, 32A, 36 and 37 is a security grille 250 which can be utilised with the present invention. The security grille 250 is mounted in a window opening 252 via a peripheral rectangular frame 254 as illustrated in fig 36. In each comer of frame 254 are comer formations 256, made up of a vertically extending members 258, which interact with a top or bottom surface of horizontally extending members 260. The anangement of members 258 and 260 is done in this way so that the hollow portion 262 of member 260 is accessible from a horizontal direction. The hollow portion 262 receives any one of the previously described latch mechanisms, examples of two of those are illustrated in fig 34 and fig 35.

Extending between all four of the hollow portions 262 is a rectangular frame 264 which has the upper and lower members 266 and 268 respectively, so that their hollow portions 270, at both sides, are adjacent and open into or face the hollow portions 262 of the members 260. The frame 264 is pivoted via the hollow portions 262 and 270 into the lower comer formulation 256 by means of pins 272 as illustrated in figure 33.

Because the structural components of the security grille 250 (apart from peripheral frame 254) are constructed from square hollow section, the pins 272 must sit in bushes 274, located in both hollow portions 270 and 262. The bushes 274 have a square outer shape 276, and a cylindrical bore 278 through it to accommodate pin 272. In figure 32A, the security grille 250 is illustrated in front elevation also showing the additional vertical bars as well as the decorative scrolls. Those portions which are movable relative to those portions which are stationary are shaded by a series of dotted shading.

As illustrated in fig 34, a locking mechanism 201 (as illustrated in fig 30) is positioned into hollow portion 262 of member 260, to secure the frame 264 at two of the four co er formations 256.

In the anangement of fig 34, the cable 16 passes through an aperture 281 in an underside wall of member 260, and then passes through the hollow portion 280 of member 258, and through a hole 8 in tne peripnerai frame 254. The hole 282 receives a ferrule 284 on the end of a sheath 280 which protects the cable 16 along its path to a trigger mechanism (not illustrated) such as trigger mechanism 50 described previously. This anangement can be utilised where it is desired to have the cable 16 proceed to its remote end starting in an upward direction from the latch mechanism 201, when the latch mechanism 201 is in a generally horizontal orientation. If a downward path were required, die locations of the pins 272 and the locking mechanism 201 would be located in the two lower comer formations 256.

If a sideways heading cable 16 were required, the arrangement of fig 35 could be used. The choice of latch mechanism used in the hollow portion 262 could be according to preference or use of the previous embodiments described could be selected to meet either design criteria or other factors.

If it were desired to have the frame 264 pivot around a vertical axis, either the peripheral frame 254 could be rotated around 90° or altematively the hollow portions 280 of members 258 are left exposed and the members 260 terminate against an outside wall of the member 258.

Illustrated in figs 38 is a double door anangement which includes doors 290 and 292. Door 290 is a door meant to be regularly opened and closed, and is in the main passageway.

However, the door 292 is, for most of its use kept closed. If desired, or for emergency means the door 292 can be locked relative to the jamb 244 by means of a latch mechanism of the previous embodiments.

In fig 38, there is included a trigger 50 attached by cable 16 to a latch mechanism 294. This latch mechanism 294 is in a horizontal attitude, and the embodiments illustrated in figs 13, 14, 15 or 16 could be utilised. However, if the latch mechanism 294 were to be positioned in a vertical orientation one of the other embodiments previously described could be utilised.

Thus, by activating the lock mechanism 294, by tensioning cable 16 by the trigger mechanism 50, the door 292 will be locked relative to the door jamb 244. If in an emergency or other situation, it is desired to open both doors either simultaneously or sequentially, the trigger mechanism 50 can be tripped retracting the lock mechanism to an unlocked position, there by unlocking door 292. Because door 290 requires door 292 to lock against, both doors 290 and 292 will be openable simultaneously. in anotner embodiment the iatch mecnanisms previously αescribed allows a door jamb, tor instance, to be releasably secured in a door frame. In which case, when the door is deadlocked relative to the door jamb, if necessary or desired, the trigger can be released thereby releasing the door jamb, allowing the door to be opened, even though the deadlock is still activated. Of course the trigger and the cabling and the latch bolt of the embodiment can be hidden, so that thieves will not activate it. One of the advantages of the above embodiments is that each of them comprises very few parts. This, together with their relatively robust nature and by the use of a pin attached to a frame member in, on or to which the latch mechanism is to be attached, results in the forces exerted on the latch member being along the axis of the latch mechanism. Because of these feature the embodiments described above are readily adaptable to miniaturisation. Described above are several embodiments of the present invention and modifications by those skilled in the art can be made thereto without departing from the scope of the present invention.

Claims

1. A locking mechanism to releasably lock or secure a moveable member relative to a stationary member, said locking mechanism including a latch member adapted to be positioned in one of said members and slidable relative thereto, said latch member being able to engage the other of said members, said latch member being biased to an unlocked position and being further characterised so that when in use the application of tension and the maintenance of said tension to a tension means, interacts with said latch member, so as to move said latch member against said bias to a locked position.

2. A locking member claimed in claim 1 wherein said tension means is of the flexible type, such as a cable or chain.

3. A locking member as claimed in claim 1 or 2 wherein said locking mechanism is further characterised by said tension means, which has one end attached to said latch member or a structure which attaches to said latch member and cooperates with a pin or pulley means attached to a member which will remain stationary as said latch member moves, said pin or pulley allowing a remote end of said tension means to proceed in a desired direction.

4. A locking mechanism as claimed in any one of the previous claims wherein said tensioning means includes a latch end which is connected to said latch member or a part of a structure connected to said latch member and a remote end away from said latch end, such that when said tensioning means is tensioned by force applied to said remote end, forces will be transfened to said latch end and thereby said latch member or said part can move against said bias, to move said latch member to a locked position.

5. A locking mechanism as claimed in any one of the preceding claims wherein said tension member passes through an opening in said latch member or a part of a structure connected to said latch member to said remote end.

6. A locking mechanism as claimed in any one of the preceding claims wherein the moveable member is a door, window, lid, cover, hatch or the like.

7. A locking mechanism as claimed in any one of claims 1 to 5 wherein the moveable member is a moveable or openable security grille.

8. A locking mechanism as claimed in any one of the previous claims wherein the stationary member is a frame adapted to be secured to a wall or other stationary means and adapted to secure the moveable or openable security grille.

9. A locking mechanism as claimed in any one of claims 1 to 7 wherein the stationary member is a window frame or door frame.

10. A locking mechanism as claimed in any one of the preceding claims wherein a tripping mechanism is used to release said tension means when required.

11. A locking mechanism as claimed in any one of the preceding claims wherein said remote end of said tension means includes a means to provide mechanical advantage for an operator.

12. A locking mechanism as claimed in any one of the preceding claims wherein the latch member and all moving parts are made from non-conosive material.