AU2010200651B2 - A latchset and a method of operating the latchset - Google Patents

Abstract

-21 Abstract A latchset which includes a first body and a second body; the first body including a first side and a cavity which extends at least partly into the first body from the first side; the second body including a first end, a retaining arrangement, a latch bolt which is movable 5 between a first position at which the bolt extends at least partly from the first end and a second position at which the bolt is engaged with the retaining arrangement and at which the first and second bodies are transversely movable relatively to each other, a mechanism with which the bolt is operable from outside of the second body and with which the bolt is movable from the first position to the second position; and wherein positioning of the first side adjacent the first 10 end causes the bolt to magnetically move from the second position to the first position so that the bolt extends at least partly into the cavity. Figure 9 64 56 54 34 Figure 10 14 - 5 Figure 11I

Description

AUSTRALIA Patents Act 1990 PATENT SPECIFICATION Invention Title: A latchset and a method of operating the latchset Applicant: Assa Abloy Australia Pty Ltd The invention is described in the following statement.

-2 TECHNICAL FIELD The invention relates generally to a latchset for an openable and a closable wing such as a door or a window. The invention may find particular application in latches of the kind commonly known as "tube latches", although the invention is not limited to this and may also 5 find application in other forms of latches or locks. BACKGROUND ART The term "latch" is generally understood by those skilled or versed in the art to refer to a device or mechanism capable of maintaining an openable and closable wing (e.g. a window or door) in a closed configuration, but which has no locking function. Hence, "latches" which provide 0 no locking function may be distinguished from "locks" which provide a locking function. As an example, in the case of a door which is provided with a latch only, closing the door may cause the door to become "latched", which will prevent it from being pushed open by wind or forced open by a child etc. However, it will generally be possible for the door to be opened from one or both sides of the door by operating the latch (e.g. by turning a latch handle etc). In 5 contrast, a "lock" provides a mechanism which can prevent the door from being opened from at least one side unless the lock is first operated (e.g. by using a key or a snib lever etc) to unlock the lock. To avoid confusion, many devices which may be referred to by a lay person as "locks", may in fact incorporate both "latch" and "lock" mechanisms, possibly within a single unit, or even as an integrated assembly providing latching and locking functions. 20 Latch mechanisms designed for use on a wing such as a door or a window takes a wide variety of forms. Some latches are mounted to an external surface of the wing, typically by attaching the latch to an inside or an outside face of the wing at a position where the latch is able to engage with a frame to which the wing is mounted or a strike/keeper mounted to the frame. Other latches are mounted in an internal cavity or "mortise" within a side edge of the wing, 25 again, in such a way that the latch is engageable with the frame or strike/keeper. One form of a conventional latch which is normally mounted in a mortise in an edge of a wing is generally referred to as a "tube latch". Figure 1 illustrates a typical tube latch 1 of a kind designed to be used with a hinged wing. A casing 2 of the latch is inserted into a mortise in a side edge of the wing, and the latch is mounted by attaching a faceplate 3 (using screws 30 inserted through the screw holes therein) to the side edge of the wing. A latch tongue 4 (also -3 commonly called a latch bolt) is movable relative to the wing between a projected "latching" position (shown in Figure 1) and a retracted position (not shown). In the latching position, the end of the latch tongue 4 extends from the faceplate 3 so that, when the wing is moved to a position at which an aperture which is defined by the frame is 5 closed by the wing (hereinafter referred to as the closed position), the end of the latch tongue 4 engages with a strike or cavity in the frame (not shown) and thereby latching the door in the closed position. Conversely, when the latch tongue 4 moves into the retracted position, a free end of the latch tongue 4 is retracted at least partially into the casing 2, thereby moving out of engagement with the strike or cavity so that wing is moveable to a position at which the 0 aperture is at least partly open (hereinafter referred to as the open position). The latch mechanism generally contains a spring (not visible) which biases the latch tongue 4 towards the extended latching position. The latch tongue 4 therefore is normally positioned in the projecting latching position. Consequently, when the wing is moved to the closed position, the projecting latch tongue 4 typically contacts with the strike of the frame as the wing is [5 moved to the closed position. When the tongue contacts the strike, a sloped end of the latch tongue 4 functions to push the tongue back into the casing 2 (against the biasing action of the spring) and it then "rides over" the strike. When the wing is at the closed position, the latch tongue is registered with the strike of the frame so that the biasing action of the spring causes the latch tongue to automatically move into the latching position in which it extends into a 20 receiving cavity in the strike. The wing is now latched closed. A latch in which the latch tongue automatically moves into the latching position when the wing moves into the closed position may be described as "self latching" as the latch does not require any additional action or manipulation by the user to adopt the latching configuration. To enable the wing to be moved to the open position, the wing typically has one or more 25 handles (not shown). In the latch I in Figure 1, the handle(s) will connect to the latch mechanism via a solid square spindle (not shown) which inserts into a square aperture 5 in a drive component 6 of the latch. Hence, rotation of the handle is transmitted via the spindle to cause corresponding rotation of the drive component 6. The drive component has a pair of camming surfaces 6' (only one of the camming surfaces 6' is visible in Figure 1 - the other is 30 hidden from view on an underside of the latch casing 2). When the drive component 6 is rotated, one of the calming surfaces 6' (depending on which direction drive component 6 is turned) is pushed against a spring biased block component 7 which is attached to the latch -4 tongue 4. Consequently, rotating the latch handle causes the drive component 6 to rotate, which in turn causes one of the camming surfaces 6' causes the block component 7 to move away from the faceplate 3, and this in turn causes the latch tongue 4 to retract at least partially into the casing 2 thereby reducing the degree of difficulty with which the wing can be moved 5 to the open position. One of the problems with conventional latches like the one illustrated in Figure 1, is that the latch tongue resides in the projected latching position almost all of the time (i.e. except when the handle is rotated to retract it, or when it is temporarily pushed back in as the wing is moved to the closed position). Therefore, when the wing is moved to the open position, it is possible 0 for clothing or other items to be hooked or snagged on the projecting latch tongue. The projecting latch tongue may also detract from the appearance of the wing when it is in the open position. Attempts have been made address the above-mentioned problems by designing alternative self latching latches such as by using magnet(s) to move the latch tongue between the retracted, un t5 latching position and the extended, latching position. Australian Patent No 2007100682 provides an example of one such latch. The latch tongue in Patent No 2007100682 is spring biased. However, unlike the latch in Figure 1 where the latch tongue 4 is spring biased towards the extended latching position, in Patent No 2007100682 the latch tongue is spring biased towards the retracted un-latching position. In Patent No 2007100682, the latch tongue contains 20 a permanent magnet and a corresponding permanent magnet is positioned inside the keeper which is mounted to the wing frame. When the wing is open, the spring maintains the latch tongue in the retracted, un-latching position. However, when the wing is closed, the latch tongue (containing a permanent magnet) comes into close proximity with the keeper (which contains the other permanent magnet). The poles of the respective magnets are oriented such 25 that the close proximity of the magnets creates an attractive magnetic force sufficient to overpower the spring bias and draws (i.e. extends) the latch tongue out into the latching position in which it engages with the keeper to retain the wing in the closed position. Further alternative self latching latches have been proposed which, again, have a permanent magnet in the latch tongue, and wherein the latch tongue is drawn out into the extended, 30 latching position when brought into close proximity with a strike containing a second permanent magnet. However, some of these alternative latches operate without a spring to bias the latch tongue towards the un-latching position when the wing is moved to the open position.

-5 An example of one such latch is given in US Patent No 3794366. In this US patent, the latch tongue is provided with a permanent magnet and the latch casing is made from a material which is magnetically attracted to the magnet in the latch tongue. Consequently, when the wing is moved to the open position, the latch tongue is retained in the retracted un-latching 5 position by the magnetic attraction between the latch casing and the magnet in the latch tongue. However, the strength of the magnetic attraction between the casing and the latch tongue is less than the strength of the attraction created between the latch tongue and the permanent magnet in the strike/keeper when the latch tongue and the keeper are brought into close proximity. Hence, when the wing is moved to the closed position, the attraction between the latch tongue 0 and the strike/keeper overpowers the attraction between the latch tongue and the casing, thus causing the latch tongue to be drawn out into the extended, latching position. Latches of the kind described hereinabove generally include mechanisms made from intricate assemblies of metal components, springs and the like. The manufacture of the various components, and their assembly to form the latch, is often labour and/or machinery intensive, 5 and consequently expensive. A latch which may be more easily and cheaply produced would therefore appear desirable. It will be clearly understood that any reference in this specification to existing latch or lock configurations or mechanisms, their operation, or associated problems, does not constitute an acknowledgement or admission that any latch or lock configurations or mechanisms, or 0 their use, or problems associated with them, or any other information whatsoever (documentary or otherwise) is/was ever common general knowledge or admissible prior art in Australia or any other country. It is an aim of the invention to provide a latchset and a method of operating the latchset which overcomes or ameliorates one or more of the disadvantages or problems described .5 above, or which at least provides the consumer with a useful choice. SUMMARY OF THE INVENTION In one form, the invention resides broadly in a latchset which includes a first body and a second body; the first body including a first side and a cavity which extends at least partly into the first body from the first side; the second body including a first end, a retaining 30 arrangement, a latch bolt which is movable between a first position at which the bolt extends at least partly from the first end of the second body and a second position at which the bolt is - 6a engaged with the retaining arrangement and at which the latch bolt is transversely movable relatively to the first body, and a mechanism with which the bolt is operable from outside of the second body and with which the bolt is movable from the first position to the second position; wherein positioning of the first side of the first body adjacent the first end of the 5 second body causes the bolt to magnetically move from the second position to the first position so that the bolt extends at least partly into the cavity and wherein the retaining arrangement is operable to hold the latch bolt in the second position by friction. In another form, the invention resides broadly in a latchset which includes two bodies, a first 0 body and a second body, one of the first or second bodies for securing to a wing and the other of the bodies for securing to a frame member adjacent the wing; the first body including a first side located facing the second body when the first and second bodies are aligned and a cavity which extends at least partly into the first body from the first side; the second body including a first end located adjacent the first body when the first and second bodies are aligned, a 5 retaining arrangement, a latch bolt movable between a latching condition in which the latch bolt extends at least partly from the first end of the second body and an un-latched condition in which the latch bolt is engaged by the retaining arrangement such that the first and second bodies are transversely movable relatively to each other, a mechanism operable from outside of the second body to move the latch bolt from the latching condition to the un-latched condition; 0 wherein aligning the first body with the second body causes the latch bolt to magnetically move from the unlatched condition to the latched condition so that the latch bolt extends at least partly into the cavity. The first body may have any suitable shape and form and may be a strike which includes a striker plate which forms the first side. 25 It is envisaged that in some particular embodiments of the invention, namely ones having a "tube latch" configuration and a multi-part housing, the second body may include two or more casing components or members which together form a housing portion of the second body, plus a fascia component or a faceplate portion which forms the first end of the housing portion from which the latch bolt projects when it is in the latching or first position. These housing 30 components may also include ridges, screw/fastener holes, and/or other sculpted or shaped features, recesses and/or apertures for mounting or operating with the latch's components, securing the housing components together, and mounting housing to a wing such as a door.

- 6b The first end may be profiled into any desired shape such as by forming the first end so that it is extends substantially perpendicularly relative to the length of the latch. Alternatively, the -.7 latch may include a faceplate which is associated with the first end in any appropriate way, for example by making use of suitable fasteners with which the faceplate is secured to the first end, or by using a suitable welding technique to attach the faceplate to the first end, and through which the latch bolt is movable between the first and second positions. The faceplate 5 may be integrally formed with the latch so that the first end is formed on the faceplate. Any suitable technique, for example magnetically or mechanically, may be used to retain the latch bolt in the second position, after the latch bolt has been mechanically moved to the second position, and which allows the latch bolt to magnetically move from the second position to the first position. For example, the retaining arrangement may include a magnet, 0 which may be a permanent magnet or a metal component which is magnetically charged by way of electricity, which magnetically maintains the latch bolt at the second position. Alternatively, an end of the latch bolt may be frictionally engaged with retaining arrangement. In this regard, the retaining arrangement may include first and second, opposed members which are movable relatively to each other and which allow the latch bolt to be moved in 5 between the opposed first and second members so that the latch bolt is frictionally secured in the second position to the retaining arrangement. The end of the latch bolt which is frictionally engaged with the retaining arrangement may be profiled to promote the frictional engagement of the latch bolt with the retaining arrangement. For example, the end of the latch bolt may include a tubular member around which the 20 retaining member can clip or otherwise engage. The latch bolt may include a spigot or pin which stands proud from an outer surface of the latch bolt, for example a side of the latch bolt, and which is frictionally engageable with the first and second, opposed members. In this configuration, the tubular member will normally extend substantially perpendicularly from the latch bolt. The first and second, opposed 25 members may have any suitable shape to promote the retention of the latch bolt in the second position by the retaining arrangement. In one embodiment of the invention, the first and second opposed members may be positioned within the second body to engage the tubular member as the latch bolt is moved into the second position. Normally, the first and second opposed members will clamp the tubular member 30 therebetween. In another embodiment of the invention, the first and second opposed members may be shaped to engage the tubular member. For example, the first and second members may -8 each have an arcuate portion positioned laterally behind (further from the first end) a protruding portion whereby, as the latch bolt is moved into second position, the tubular member is forced past the respective protruding portions and is located between the respective arcuate portions. Typically, the first and second opposed members are resilient and will 5 normally be deformed as the tubular member passes the respective protruding portions with the resilience of the first and second opposed members holding the tubular member therebetween with sufficient force to prevent accidental dislodgement but with less force than the magnetic force applied when the first and second bodies are aligned. The mechanism to move the latch bolt to the second position or un-latched condition may 0 include a lever which is attached to the latch bolt and with which the latch bolt is movable from the first or latched position to the second, un-latched position. The lever may be in the form of a snib or a handle. The mechanism may include a drive component, a handle, and a spindle which extends between the drive component and the handle so that rotational movement of the handle is transferred to the drive component. .5 The latch bolt may include at least a first bearing surface and the drive component may include at least a first cam which acts against the at least first bearing surface so that rotational movement of the drive component causes the latch bolt to move to the second position. Other configurations such as interleaved toothed bodies may be used. The latch bolt may take any suitable configuration which enables it to engage with the !0 associated first body or strike when in the latching or first position. Suitably, the latch bolt, or at least the portion of it which projects from the first end when in the first position, may have a generally tubular configuration adapted to be received in the cavity or recess in the first body or strike. The shape of the cavity may roughly correspond with the shape of the latch bolt (or portion thereof) adapted to be received therein. The latch bolt may have a generally flat end 25 which can become positioned flush (or approximately so) with the first end of the latch, or with the faceplate of the latch, when the latch bolt is in the un-latched or second position. This may assist with preventing clothing and other loose items from snagging on a latch tongue or the latch bolt, and it may also improve the overall aesthetic of the side edge of the latch when exposed to view. 30 The latchset may include one or more magnets which may be arranged in any appropriate way to cause the latch bolt to move magnetically from the second position to the first position. For example, a blind end of the cavity in the first body (adjacent the first side) may include a -9 magnet which, when the first side of the first body is positioned adjacent the first end of the second body, magnetically attracts the free end of the latch bolt, which should include a metal component or which, in a preferred way, may be made entirely from a metalliferous material, so that the latch bolt is magnetically pulled from engagement from the retaining arrangement 5 and is caused to move from the second position to the first position. Conversely, the blind end of the cavity may include a metalliferous material or may be manufactured entirely from a metalliferous material, and the free end of the latch bolt may include a magnet which is attracted the metalliferous component of the blind end so that when the latch bolt is brought into close proximity to the first body, the magnet of the latch bolt 10 magnetically pulls it towards the blind end which causes disengagement of the latch bolt from the retaining arrangement. Alternatively, both the blind end of the cavity and the free end of the latch bolt may include a suitable magnet so that the latch bolt is magnetically moved from the second position to the first position as a result of the magnetic attraction formed between these two magnets. 15 The different components of the latchset may be made from any material which is rigid and robust enough to be used in the manufacture of the latch and the strike which can sometimes be required to endure moderate shock loading and impacts, e.g. when a door to which the latch is mounted is slammed into a frame to which the strike is mounted or when the mechanism is operated roughly or vigorously). 20 Suitable materials may include steel and other metal alloys, and polymer materials such as engineering plastics with sufficiently high strength and fatigue resistance. It is preferred that the components of the latchset should be made from a polymer material of this kind as the cost of manufacturing the components from these materials may be lower than the cost of producing similar components from metal. The polymer materials may also be somewhat 25 more flexible than metal. Moulding such as injection moulding, or any other suitable manufacturing technique may be used to make any polymer or plastic components. Whilst the housing components may be made from a polymer material, it is envisaged that the fascia component may often be made from a slightly more robust material, typically a metal alloy. The reason a somewhat more robust material may be used for the fascia component is 30 because the fascia component may often be mounted with at least a part of it exposed on the side edge of a wing such as a door for example, and it may therefore be directly exposed to - 10 impacts, for example possible contact between the fascia component and the strike when a door is slammed etc. In a second form, the invention resides broadly in a wing assembly which includes a frame which defines an aperture, at least one wing which is movably mounted to the frame and which 5 is movable between a open position at which the aperture is at least partly open and a closed position at which the aperture is covered by the door, and a latchset which secures the door in the second position; the latchset including a strike which is secured to the frame and which includes a cavity which extends at least partly into the strike, and a latch which includes a first end, a retaining arrangement, a latch bolt which is movable between a first position at which 10 the latch bolt extends from the first end and a second position at which the latch bolt is engaged with the retaining arrangement, and a mechanism with which the latch bolt is movable to the second position from outside of the wing, and wherein movement of the wing to the first position causes the latch bolt to magnetically move from the second position to the first position so that the latch bolt at least partly extends into the cavity thereby securing the wing in 15 the second position. The frame may be constructed in any appropriate, for example the components of the frame may be welded to each other or secured to each other by way of suitable fasteners such as nuts and bolts or screws, and may be manufactured from any suitable material such as a metal, plastics, or wood. The frame may be constructed to be freestanding or may be secured to a 20 wall. The wing may be any suitable component which can be used to close the aperture of the frame and may be selected from any one of the following: a door and a window. The wing may be manufactured from any suitable material such as a metal, plastics or wood. The strike may be secured to the frame in any appropriate way. For example, the strike may be 25 embedded, at least partly, in the frame or may be secured to an exterior surface of the frame. The strike may be secured to the frame using techniques known in the art such as by using one or more rivet, screws, or a nut and bolt. Similarly, the latch may be secured to the wing in any appropriate way. For example, the latch may be embedded, at least partly, in the wing or maybe be secured to an exterior surface of the 30 wing. Typically the latch will be secured to the wing in substantially the same way in which the strike has been secured to the frame, for example if the latch is embedded at least partly in 10 a impacts, for example possible contact between the fascia component and the strike when a door is slammed etc. In another form, the invention resides broadly in a wing assembly (e.g. a door assembly) which includes a frame which defines an aperture, at least one wing which is movably mounted to the 5 frame and which is movable between an open position at which the aperture is at least partly open and a closed position at which the aperture is covered by the wing, and a latchset which secures the door in the closed position; the latchset including a strike which is secured to the frame and which includes a cavity which extends at least partly into the strike, and a latch which is secured to the wing and which includes a first end, a retaining arrangement, a latch 0 bolt which is movable between a first position at which the latch bolt extends from the first end and a second position at which the latch bolt is engaged with the retaining arrangement, and a mechanism with which the latch bolt is movable to the second position from outside of the wing, wherein movement of the wing to the closed position causes the latch bolt to magnetically move from the second position to the first position so that the latch bolt at least 5 partly extends into the cavity thereby securing the wing in the closed position and wherein the retaining arrangement is operable to hold the latch bolt in the second position by friction. The frame may be constructed in any appropriate, for example the components of the frame may be welded to each other or secured to each other by way of suitable fasteners such as nuts and bolts or screws, and may be manufactured from any suitable material such as a metal, 0 plastics, or wood. The frame may be constructed to be freestanding or may be secured to a wall. The wing may be any suitable component which can be used to close the aperture of the frame and may be selected from any one of the following: a door and a window. The wing may be manufactured from any suitable material such as a metal, plastics or wood. 25 The strike may be secured to the frame in any appropriate way. For example, the strike may be embedded, at least partly, in the frame or may be secured to an exterior surface of the frame. The strike may be secured to the frame using techniques known in the art such as by using one or more rivet, screws, or a nut and bolt. Similarly, the latch may be secured to the wing in any appropriate way. For example, the latch 30 may be embedded, at least partly, in the wing or maybe be secured to an exterior surface of the 10 b wing. Typically the latch will be secured to the wing in substantially the same way in which the strike has been secured to the frame, for example if the latch is embedded at least partly in - I1 the wing, then the strike will be embedded at least partly in the frame so that the strike and the latch can be properly aligned in order for the latchset to function optimally. In yet another form, the invention resides broadly in a method of operating a latchset which includes a strike having a cavity which at least partly extends into the strike, and a latch which 5 includes a first end, a retaining arrangement, a latch bolt which is movable between a first position at which the latch bolt extends at least partly from the first end and a second position at which the latch bolt is engaged to the retaining arrangement, and a mechanism with which the latch bolt is movable from the first position to the second position from an outside of the latch; the method including the steps of operating the mechanism thereby causing the latch bolt 0 to move from the first position to the second position and thereby to engage with the retaining arrangement so that the latch is transversely movable relatively to the strike; and positioning the first end adjacent the cavity thereby causing the latch bolt to magnetically move from the second position to the first position so that the latch bolt at least partly extends into the cavity and thereby prevents transverse movement of the latch relative to the strike, and wherein the 5 retaining arrangement is operable to hold the latch bolt in the second position by friction. BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be more readily understood and be more readily put into practice, one or more preferred embodiments thereof will now be described, by way of example, with reference to the accompanying drawings in which: 0 Figure 1 is a perspective view of a tube latch which is known in the art; Figure 2 is a perspective view of a latchset according to the invention; Figure 3 is an exploded, perspective view of the latchset; Figure 4 is a schematic representation of a latchset which is secured to a frame and a door which has been movably mounted to the frame; 25 Figure 5 is a side view of the latch with a latch bolt thereof in an unlatching or second position; Figure 6 is a plan view, in cross-section, of the latch of Figure 5 taken on a line 6 - 6 in Figure 5; Figure 7 is a side view of the latch with the latch bolt in a latching or first position; - 12 Figure 8 is a plan view, in cross-section, of the latch of Figure 7 taken on a line 8 - 8 in Figure 7; Figure 9 is a perspective view, in cross-section, of the latch shown in Figure 7; Figure 10 is a perspective view, in cross-section, of the latch in which the latch bolt is 5 partly moved to the unlatching position; and Figure 1I is a perspective view, in cross-section, of the latch shown in Figure 5. DETAILED DESCRIPTION OF THE DRAWINGS Figure 2 of the accompanying representations illustrates a latchset 10 according to the invention which includes a first body or strike 12 and a second body or latch 14 which has a 10 general "tube latch"-type configuration which is roughly similar to that of the prior art latch I described in the background section hereinabove. Like the prior art latch 1, the latch 14 is suitable for use with hinged doors and windows (although it may also be suitable for other uses). The strike 12 has a first side 16 which is on a striker plate 18 and a cavity 20 which extends at 15 least partly into the strike from the first side through the striker plate. The strike may be manufactured from any suitable material such as a metal or a plastic. The latch has a first end 22, a retaining arrangement 24, a latch bolt 26 which is movable between a first position 28 (which is shown in Figures 7, 8 and 9) in which the latchset is in a latched condition and a second position 30 in which the latchset is in an un-latched condition 20 and which is shown, for example, in Figure 6, and a mechanism 32 which is shown in part in Figure 2 and through which the latch bolt is operable from outside of the latch so that the latch bolt is movable from the first position to the second position. The components of the latchset 10 is manufactured from any suitable material such as a metal or plastic which is rigid and robust enough to be used in a latchset bearing in mind that the 25 latchset can sometimes be required to endure moderate shock loading and impacts such as when a door is slammed closed or when the mechanism 32 is operated roughly or vigorously. Suitable materials may include steel or other metal alloys, and polymer material such as engineering plastics with a sufficiently high strength and fatigue resistance. It is preferred that the components should be made from a polymer material of the latter kind as the cost of 30 manufacturing the components from these materials may be lower than the cost of producing - 13 similar components from metal. The polymer materials may also be somewhat more flexible than metal. Moulding such as injection moulding, or any other suitable manufacturing technique, may be used to make any polymer or plastic components. While some parts of the latchset 10 may be made from a polymer material, it is preferred that 5 components which are exposed to the environment, for example the first end 22 and the striker plate 18, be made from a slightly more robust material, typically a metal alloy. These components may often be mounted with at least a part of it exposed, and it may therefore be directly exposed to impacts, for example when a component to which the latch 14 is mounted is slammed into a component to which the striker 12 is mounted. 10 The components used in the construction of the latchset 10 are shown in greater detail in Figure 3. The latch 14 includes a faceplate portion 34 and a housing portion 36 which is secured to the faceplate portion by way of a pair of clips 38 which are registered with a pair of slots 40 which have been made at suitable locations on the faceplate portion. The housing portion includes a first member 42 and an opposed second member 44. The first and second 15 members are not secured to each other, for example by using screws or a plurality of nuts and bolts. This reduces the degree of difficulty with which the latch can be disassembled and reassembled when required. The correct alignment of the first and second members 42 and 44 relatively to each other is achieved with a plurality of pins 46, which in this example extends from the second member 44, which are registered with a plurality of holes 48 which are formed 20 in the first member 42. Additionally, the first and second members each contain a shoulder formation 50 which further enhances the correct positioning of the first and second members relatively to each other. The first and second members 42 and 44, once engaged with each other, define a chamber 52 in which the latch bolt 26 is slidingly mounted so that the latch bolt is movable between the 25 first position 28, which is shown in Figures 7, 8 and 9, and the second position 30 which is shown in Figure 2, 5, 6, and 11. The latch bolt includes a pin 54 which is frictionally engages with first and second clip members 56 and 58 of the retaining arrangement 24. The first and second clip members, when the housing portion 36 is assembled, define a cavity 60 in which the pin is located when the latch bolt is moved to the second position 30. Each of the clip 30 members has a free end 62 which is flared thereby facilitating the movement of the pin between the first and second clip members.

- 14 Only part of the mechanism 32 is shown in the accompanying representations. However, the construction and operation of the mechanism is substantially conventional in nature and, for this reason, only the components and operation of the mechanism required for the understanding of this invention are described in greater detail hereinafter. 5 The mechanism 32 has a drive component 64 which is rotatably mounted inside the housing portion 36. A pair of cams or shoulder formations 66 extends from a side of the drive component. The latch bolt 26 has a pair of bearing surfaces 68 against which the pair of shoulder formations act when the drive member is rotated inside the housing portion. The mechanism further includes a pair of handle components and a spindle, all of which not shown. 10 The spindle extends through the square passage 70 of drive component and is engageable at opposed ends a handle component so that rotational movement of either handle component is transferred via the spindle to the drive component. Typically each of the handle components is biased, for example making use of a suitable spring mechanism, to a neutral position in which a handlebar of the respective handle component extends substantially horizontally. As a result, 15 the drive component will normally be in an orientation which is shown in Figure 3 when neither of the handle components is operated. The latch bolt 26 includes a latch tongue 72 at a free end 74 thereof. A first magnet 76 is secured to the latch tongue using any suitable technique which is known in the art, for example using a resin or glue or by crimping the latch tongue onto the magnet. 20 The faceplate portion 34 forms the first end 22 of the latch 14 and is profiled so that the first end is substantially planar and includes a faceplate 78 which may have a pair of holes 80 which can accommodate a pair of screws, not shown, so that the faceplate portion, and thereby the latch, is securable to structure such as a door, not shown. The faceplate portion further includes a passage 82 which extends therethrough from the faceplate so that, once the housing 25 portion is engaged using the pair of clips 38 with the faceplate portion, part of the latch bolt 26 is located inside the chamber 52 and a part of the latch bolt is located inside the passage 82. The latch tongue 72 has a length 84 which is such that when the latch bolt is in the second position 30, the free end 74 is in line with the first side 16 thereby forming a planar surface 86 (see Figure 2). 30 The cavity 20 has a blind end 88 to which a second magnet 90 is secured using a plurality of clips 92.

-15 The striker plate 18 has a pair of holes 94 which can accommodate a pair of screws, not shown, so that the striker plate, and thereby the strike 12, is securable to a structure such as a frame. Figure 4 shows the latchset 10 being secured to a frame 100 and to a door 102 which is movably mounted to the frame. Suitable apertures have been made using techniques known in 5 the art in respectively the frame and door so that the latch 14 can be inserted into the door and the strike into the frame so that the first end 22 aligns substantially with a side 104 of the door and the first side 16 aligns substantially with an inner surface 106 of the frame. In this figure the door is shown to be in a closed position at which an aperture which is defined by the frame is closed by the door. This is typically achieved by aligning the side 104 of the door with the 10 inner surface 106 of the frame. The door is movable to an open position at which the aperture is at least partly open. This aspect of the invention, i.e. the opening and closing of the aperture of the frame with a door, is substantially conventional in nature and for this reason are not further described in greater detail hereinafter. The operation of the latchset is shown in greater detail in Figures 5 to 11. The latch bolt 26 is 15 shown in the first position 28 in Figures 7, 8 and 9 and in the second position 30 in Figures 5, 6 and 11. In Figure 10, the latch bolt is shown as partly being mechanically moved from the first position to the second position through the operation of the mechanism 32. During normal operation of the latchset, the latch bolt 26 is mechanically moved from the first position 28 to the second position 30 through the operation of the mechanism 30 and is 20 magnetically moved from the second position to the first position by bringing the first and second magnets 76 and 90 into close proximity to each other. Referring in particular to Figure 10, operating one of the handle components of the mechanism 30 causes the drive component 64 to rotate which results in one of the shoulder formations 66 to act against one of the bearing surfaces 68 so that rotational movement of the drive 25 component pulls the latch bolt into the chamber 52. As the latch bolt is moved into the chamber, at some point the pin 54 engages with the retaining arrangement 24 and moves in between the first and second clip members 56 and 58. This movement is facilitated by the respective flared free ends 62 of the first and second clip members. By rotating the respective handle component to a maximum extent, results in the pin to be aligned with the cavity 60 so 30 that the latch bolt 26 is engaged with, and secured to the retaining arrangement 24. The door 102 can now be moved relatively to the frame 100, for example by opening the door. The latch bolt 26 is now at the second position which is shown in 5, 6 and 11.

- 16 The magnetic attraction between the first and second magnets 76 and 90 will be the strongest when the door 102 is moved to the closed position, i.e. by moving the door to a position at which the side 104 of the door substantially aligns with the inner surface 106 of the frame (as shown in Figure 4). The increase in magnetic attraction is as a result of a distance 108 between 5 these magnets being reduced to a minimum. At this point the magnetic attraction between the first and second magnet is sufficient to overcome the fictional engagement of the spigot 54 with the first and second clip members 56 and 58 of the retaining arrangement 24 and the spigot is magnetically moved from the second position 30 to the first position 28 as he shown in 7, 8 and 9. The latch bolt now extends into the cavity 20 so that the door is latched to the 10 frame and is prevented from being moved relatively to the frame. A side 110 of the latch bolt 26 is not tapered (see Figure 8) so that, when the latch bolt is in the first position 28, it is not possible to disengage the latch bolt from the strike 12, for example, by gripping one of the handle components of the mechanism 32 and to try and open the door 104 without first having rotated the handle component to a sufficient extent so that the latch 15 bolt has been withdrawn completely from the cavity 20. Thus, the latch bolt is moved from the first position to the second position 30 through the operation of the mechanism 32. A mechanical force is therefore required to move the latch bolt from the first position to the second position which is generated through rotational movement of the drive component 64 which, in turn, is caused by rotating a respective handle component of the mechanism 32. 20 In other words, the latch bolt 26 is not automatically moved from the first position 28 to the second position 30 when a pulling force is exerted on the door through one of the handle components. Before such a force is applied to the respective handle component, a rotation force must be first applied to this handle component to cause the latch bolt to move to the second position 30. 25 However, the latch bolt 26 is automatically moved from the second position 30 to the first position 28 as a result of the magnetic attraction between the first and second magnets 76 and 90. The magnitude of the magnetic attraction is only greater than the magnitude of the fictional force which exists between the first and second clip members 56 and 58 and the spigot 54 when the side 104 is brought into close proximity to the inner surface 106. Thus, the latch 30 bolt is only moved from the second position to the first position when the door 102 is closed. It should be noted that when a user, not shown, has moved the latch bolt 26 from the first position 28 to the second position 30 by rotating a handle component of the mechanism 32, and - 17 thereafter allows the handle component to move to the neutral position without moving from the the door 102 away from frame 100 (in other words, by keeping the door closed), the magnetic attraction between the first and second magnets 76 and 90 will cause the these two magnets to move towards each other which will result in the latch bolt being moved to the first 5 position so that the door is once again latched to the frame. The latch bolt of the latchset of the present invention is withdrawn into the latch of the latchset so that the first end of the latch is substantially planar thereby reducing the likelihood of clothing or other items to be hooked or snagged on to the latch tongue. The latch bolt is withdrawn into the latch through rotational movement of one of the handle components of the 10 mechanism thereby reducing the likelihood of the door accidentally being opened when only a pulling force is applied to the door. The door is also automatically latched to the frame when the door is closed thereby reducing the likelihood of human error causing the door not been properly latched, or in a worst-case scenario not latched at all. The latch and strike are also assembled using a series of clips, pins which are registered with counterpart holes, and 15 shoulder formations which reduces the degree of difficulty in assembling and disassembling the latchset when required, for example when replacing a broken part. The latchset further has a simple construction so that the components of the latchset can be assembled without a great degree of difficulty. The foregoing embodiments are illustrative only of the principles of the invention, and various 20 modifications and changes will readily occur to those skilled in the art. The invention is capable of being practiced and carried out in various ways and in other embodiments. It is also to be understood that the terminology employed herein is for the purpose of description and should not be regarded as limiting. The term "comprise" and variants of the term such as "comprises" or "comprising" are used 25 herein to denote the inclusion of a stated integer or stated integers but not to exclude any other integer or any other integers, unless in the context or usage an exclusive interpretation of the term is required. Any reference to publications cited in this specification is not an admission that the disclosures constitute common general knowledge in Australia.

Claims (16)

1. A latchset which includes a first body and a second body; the first body including a first side and a cavity which extends at least partly into the first body from the first side; the 5 second body including a first end, a retaining arrangement, a latch bolt which is movable between a first position at which the bolt extends at least partly from the first end and a second position at which the bolt is engaged with the retaining arrangement and at which the latch bolt is transversely movable relatively to the first body, and a mechanism with which the bolt is operable from outside of the second body and with which the bolt is 0 movable from the first position to the second position; wherein positioning of the first side adjacent the first end causes the bolt to magnetically move from the second position to the first position so that the bolt extends at least partly into the cavity and wherein the retaining arrangement is operable to hold the latch bolt in the second position by friction.

2. The latchset according to claim 1 wherein the retaining arrangement includes a clamping 5 mechanism having first and second, opposed members which are movable relative to each other and which allow the latch bolt to be moved so that the latch bolt is frictionally secured in the second position.

3. The latchset according to claim 2 wherein the opposed first and second members are resiliently deformable and biased into a clamping condition. 0

4. The latchset according to either one of claims 2 or 3 wherein the latch bolt is associated with a retaining member adapted to be frictionally engaged with the opposed first and second members when the latch bolt is moved to the second position.

5. The latchset according to any one of the preceding claims wherein the mechanism with which the bolt is operable from outside of the second body includes a lever handle operable 25 externally of the second body to move the latch bolt to the second position.

6. The latchset according to any one of the preceding claims wherein the latch bolt includes a rear portion having at least one bearing surface in order to be movable to the second position.

7. The latchset according to claim 6 wherein the rear portion of the latch bolt has a pair of 30 elongate spaced apart arms, one upper and one lower, each having an opening therein which forms a portion of the at least one bearing surface.

8. The latchset according to claim 7 wherein the second body includes a drive component including at least a first cam portion which acts against the at least one bearing surface - 19 during rotation, and a shaped bore to receive a spindle so that rotational movement of the drive component causes the latch bolt to move to the second position.

9. The latchset according to claim 8 wherein each opening has a bearing member associated therewith at a rearward end. 5

10. The latchset according to claim 9 wherein the drive component has a pair of cam portions, each of which abuts one of the bearing members when the latch bolt is in the first position.

11. The latchset according to any one of claims 8 to 10 wherein the drive component is mounted for rotation within the second body and is separate from but engageable with the latch bolt. 0

12. The latchset according to any one of the preceding claims wherein the latch bolt includes a forward portion adapted to mount a magnetically effected body.

13. The latchset according to any one of the preceding claims wherein the first body includes a magnetically effected body.

14. The latchset according to either claim 12 or 13 wherein the magnetically effected body is a 5 magnet.

15. A door assembly which includes a frame which defines an aperture, a wing which is movably mounted to the frame and which is movable between an open position at which the aperture is at least partly open and a closed position at which the aperture is covered by the wing, and a latchset which secures the wing in the closed position; the latchset 0 including a strike which is secured to the frame and which includes a cavity which extends at least partly into the strike, and a latch which is secured to the wing and which includes a first end, a retaining arrangement, a latch bolt which is movable between a first position at which the latch bolt extends from the first end and a second position at which the latch bolt is engaged with the retaining arrangement, and a mechanism with which the latch bolt is 25 movable to ihe second position from outside of the wing, wherein movement of the wing to the closed position causes the latch bolt to magnetically move from the second position to the first position so that the latch bolt at least partly extends into the cavity thereby securing the wing in the closed position and wherein the retaining arrangement is operable to hold the latch bolt in the second position by friction. 30

16. A method of operating a latchset which includes a strike having a cavity which at least partly extends into the strike, and a latch which includes a first end, a retaining arrangement, a latch bolt which is movable between a first position at which the latch bolt extends at least partly from the first end and a second position at which the latch bolt is -20 engaged to the retaining arrangement, and a mechanism with which the latch bolt is movable from the first position to the second position from an outside of the latch; the method including the steps of operating the mechanism thereby causing the latch bolt to move from the first position to the second position and thereby to engage with the retaining 5 arrangement so that the latch is transversely movable relatively to the strike; and positioning the first end adjacent the cavity thereby causing the latch bolt to magnetically move from the second position to the first position so that the latch bolt at least partly extends into the cavity and thereby prevents transverse movement of the latch relative to the strike, and wherein the retaining arrangement is operable to hold the latch bolt in the 0 second position by friction.