WO 2005/041724 PCT/AU2004/001441 Latch Mechanism Field of the invention The present invention relates to a latch mechanism for furniture. More particularly it relates to a latch mechanism for furniture having a panel, wall or similar component that is slidably moveable relative to the other parts of the furniture. For example, the latch mechanism of the present invention may be suitable for furniture such as a child's cot having one or more sides that can be moved vertically relative to either end of the cot. Background of the invention In this specification where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date publicly available, known to the public, part of the common general knowledge, or known to be relevant to an attempt to solve any problem with which this specification is concerned. Whilst the following description relates to a child's cot, it will be appreciated that the invention is not so limited and could relate to other furniture such as cribs, or hospital beds having a panel, wall or other generally planar component that is slidably moveable. Children's cots are common furniture items in homes where small children live. Typically a cot is a simple, small, rectangular bed having 2 fixed ends, and 2 high sides, usually enclosing a mattress or other bedding. The sides and ends are designed to stop a child falling or climbing from the cot. The sides may be solid, but more typically they are of open construction so the child can see out. Typically the sides consist of a rectangular frame supporting a series of vertical wooden rods. The sides of the cot must be deep enough to ensure the child cannot fall or climb out, however if the sides are too deep it may be difficult for an adult to lift the child in and out of the cot. Accordingly it is common for one of the sides of the cot to be moved out of position in order to allow ready access to the interior of the cot. Typically the side is able to be vertically slid into and out of position. Although cots are freely available and widely used, almost all cots suffer from a range of deficiencies related to the sliding side mechanism. Typical safety issues are described in Australian New Zealand cot standard, Cots for household use - Safety requirements (AS/NZ 2172:1995). Some cots fail to satisfy the requirements of the safety standard.
WO 2005/041724 PCT/AU2004/001441 -2- For example, one of the problems associated with cots of the prior art is that the mechanism by which the side slides into and out of position provides projections or recesses that could be used as a foothold by a child trying to climb out of the cot. Some sliding side mechanisms do not satisfy the safety standard because they have gaps in which a child can trap a finger or toe. It is also important that the mechanism for the sliding side automatically locks in position and cannot be released by a child who pushes or falls against it, yet the side must be quickly and easily operated by an adult. Clearly, addressing the requirements of safety standards for cots will have many practical, commercial and social advantages. It has now been found that a mechanism for a sliding side can be provided that is safer and easier to use than mechanisms of the prior art. Summary of the invention According to one aspect of the present invention there is provided a sliding latch mechanism for a piece of furniture having a slidable member, the latch mechanism comprising: (a) a fixed slide rail; (b) a retractable latch adapted to removably engage the fixed slide rail; and (c) an activating means for initiating disengagement of the retractable latch from the fixed slide rail so that the slidable member can be moved between a first position and a second position; wherein in use, the retractable latch is located entirely within the slidable member. Typically the slidable member is a generally planar. For example the slidable member may be a panel or a frame having vertical or horizontal bars. With reference to a cot, the slidable member may comprise a square or rectangular side which can be moved between a first, fully raised position and a second, fully lowered position. Preferably, the latch is located entirely within a vertical edge of the slidable member. The latch is thus protected from interference or damage and the appearance of the furniture is enhanced by concealment of the working parts. More importantly, concealment of the latch avoids protrusions which may present footholds for a child in the cot. Concealment also avoids the risk of a child catching their fingers or toes in the mechanism, or WO 2005/041724 PCT/AU2004/001441 -3 contacting a part of the mechanism so as to cause unexpected retraction of the latch and movement of the side When the furniture item is a cot, typically the fixed slide rail is permanently attached to the cot frame or ends by permanent mechanical fasteners. When the cot side is in the fully raised position, the vertical edges abut the fixed ends of the cot (that is, the headboard and footboard). Typically a sliding plate or similar mechanism is movably attached to the sliding rail and fixed to the ends of the slidable member such that the slidable member is free to move vertically but not horizontally with respect to the fixed ends of the cot. Preferably, in use the fixed slide rail is also concealed within the slidable member. Typically the fixed slide rail is concealed irrespective of whether the slidable member is in the first position, the second position or any position between these two extremes. This further reduces hazards and improves cot safety. Typically the latch is adjacent the upper part of the slidable member and pivots into and out of engagement with the slide rail. The latch may be biased towards engagement of the slide rail by a spring or other suitable biasing means. In the engaged position, the latch rests on an uppermost end of the slide rail, or engages a recess in the slide rail and is prevented from moving downward by its contact with the end or recess. The actuator initiates retraction of the latch. When the latch is retracted, it disengages from the slide rail and can to slide vertically down the slide rail without interference. The actuator may act directly or indirectly on the retractable latch to cause it to retract. Typically the actuator is integral with the latch. If the retractable latch is biased towards engagement with the slide rail by a biasing means, the actuator may provide a counter force to the bias. In a preferred embodiment two retractable latches are used on opposite edges of the slidable member. The actuator may be any suitable mechanical device. Preferably it is fully or at least partially located within the slidable member. Typically the actuator is operated by a button or lever located adjacent a surface, preferably an edge of the slidable member. Alternatively, the actuator may be remotely operated. In one embodiment of the present invention the actuator is connected to the latch by a cable. In this embodiment the actuator may be foot operated. This embodiment has the advantage that the actuator can be kept away from the cot, out of reach of a child in the cot.
WO 2005/041724 PCT/AU2004/001441 -4 In a preferred embodiment, when the slidable member is a side for a cot, it may be moved between a first position, in which it is fully raised and a second position in which it is fully lowered. In the fully raised position, it provides a barrier to a child falling or climbing from the cot. In the fully raised condition it cannot be pushed downward. It may be moved from the fully raised condition by slightly lifting the side then using the actuator to retract the one or more latches. Preferably this operation requires 2 hands to raise the side slightly and to simultaneously operate the actuator. Alternatively, each latch can be disengaged by two individual single-handed operations if, for instance, a sleeping infant is being cradled in one arm, leaving only one hand free. The sliding side is then free to move vertically downward until it rests against a stop which may be incorporated in the slide rail or take the form of a separate buffer, rest or detente. Fully lowering the side provide easy access for an adult wishing to put a child in the cot or lift them out of the cot. From the fully lowered position the side can be manually lifted to the fully raised position. In this position the latch re-engages the slide rail and is held by interference with the top of the slide rail or a recess in the slide rail. This interference resists non-deliberate downward movement. The present invention has the added advantage of providing an easy means for converting a cot to a cot bed and thus allowing the one piece of furniture to be used for a baby, then modified for use as the baby becomes a toddler. Specifically, the sliding side and slide rail can be readily removed in their entirety using a single tool, such as a screwdriver. This leaves frame of the cot, such as the head board and foot board with little or no sign that they ever supported fittings and fixtures. Description of the drawings The invention will now be further explained and illustrated by reference to the accompanying drawings in which: Figure 1 is a side view of a portion of a child's cot with the sliding side in the fully raised position; Figure 2 is a side view of a portion of a child's cot with the sliding side in the fully lowered position; WO 2005/041724 PCT/AU2004/001441 -5 Figure 3a is a longitudinal section through the frame of the cot depicted in Figure 1 with the sliding side in the fully raised position and revealing one embodiment of the latch mechanism of the present invention; Figure 3b is an enlarged view of the mechanism within the circled area of Figure 3a; Figure 4a is a longitudinal section through part of the frame of the cot depicted in Figure 1 with the sliding side in the fully raised position, just prior to lowering; Figure 4b is an enlarged view of the mechanism within the circled area of Figure 4a; Figure 5a is a longitudinal section through part of the frame of the child's cot depicted in Figure 2 with the sliding side in the fully lowered position; Figure 5b is an enlarged view of the mechanism within the circled area of Figure 5a; Figure 6a is a longitudinal section through part of the frame of a cot showing a further embodiment of the latch mechanism of the present invention when the sliding side is in the fully raised position; Figure 6b is an enlarged view of the mechanism within the circled area of Figure 6a; Figure 6c is an enlarged view of the mechanism within the circled area of Figure 6a when the sliding side is in the fully lowered position; Figure 7a is a longitudinal section through part of the frame of a cot showing a further embodiment of the latch mechanism of the present invention when the sliding side is in the fully lowered position; Figure 7b is an enlarged view of the mechanism within the circled area of Figure 7a. Figure 1 is a side view of a portion of a child's cot with the sliding side in the fully raised position. The cot incorporates one embodiment of the latch mechanism of the present invention. In this view the sliding side (1) is in the fully raised condition and one edge abuts the frame of the cot headboard (2). The sliding side consists of a rectangular frame enclosing multiple parallel wooden bars. The only part of the latch mechanism that can be seen in this position is the button (3) for operating the actuator. All other components of the latch mechanism are concealed by the cot structure.
WO 2005/041724 PCT/AU2004/001441 -6 Figure 2 is the same view as Figure 1, depicting the sliding side in the fully lowered position. As per Figure 1, the only part of the latch mechanism that can be seen is the button (3) for operating the actuator. All other components of the latch mechanism are concealed by the cot structure. Figure 3a is a longitudinal section through the frame of the cot depicted in Figure 1 with the sliding side (1) in the fully raised position. In this embodiment the button (3) and actuator is integral with the latch (5). A spring (not shown) biases the latch towards engagement with the slide rail (6). The slide rail (6) is fixed at either end to the headboard of the cot. A pivot pin (8) that attaches the latch to the sliding side (1). When the actuator button (3) is pushed downwards, the latch rotates about the pivot pin (8). As illustrated in Figure 3a, when the sliding side is in the fully raised position the latch (5) rests against the top of the slide rail (6) such that the vertical load of the sliding side (1) is supported on the slide rail (6). For clarity, a portion of the latch mechanism is enlarged in Figure 3b. Figure 4a is a longitudinal section through part of the frame of the cot depicted in Figure 1 with the sliding side (1) in the fully raised position, just prior to lowering. In this view the sliding side (1) has been manually raised slightly above the position shown in Figure 3a so that the vertical load has been taken off the slide rail (6). Furthermore, the button (3) of the actuator has been pushed downwards, causing the latch (5) to rotate about the pivot pin (8) retracting the latch (5) clear of the slide rail (6). The sliding side (1) is thus free to be moved vertically downwards. For clarity, a portion of the latch mechanism is enlarged in Figure 4b. Figure 5a is a longitudinal section through part of the frame of the child's cot depicted in Figure 2 with the sliding side in the fully lowered position. In this view, the button (3) of the actuator is no longer being operated and the latch (5) is free to rotate about the pivot pin (8) and is urged back into engagement with the slide rail (6) by the biasing means (not shown). For clarity, a portion of the latch mechanism is enlarged in Figure 5a. The sliding side may stay indefinitely in the fully raised position shown in Figure 2 or the fully lowered position shown in Figure 5 until the user desires to change from one position to the other. Figure 6a is a longitudinal section through part of the frame of a cot showing a further embodiment of the latch mechanism of the present invention. In this embodiment the actuator again includes a manually operable button (13) located in the top of the frame of WO 2005/041724 PCT/AU2004/001441 -7 sliding side (11) acting on a rod (14) which contacts the latch (15) when the sliding side (11) is in the fully raised position. In the fully raised position the latch (15) rests against the top of the slide rail (16) such that all of the vertical load of the sliding side (11) is supported on the slide rail (16). The slide rail (16) is fixed at the top and bottom to the headboard of the cot. A slide plate (20) is fixed to the sliding side (11) and encircles the slide rail (16) so that the sliding side (11) may slide vertically with the sliding side (11) but horizontal movement of the sliding side (11) is resisted. For clarity, a portion of the latch mechanism is enlarged in Figure 6b. The same portion of the latch mechanism is shown in Figure 6c, the sliding side being in the fully lowered position. Figure 7a is a longitudinal section through part of the frame of a cot showing a further embodiment of the latch mechanism of the present invention. In this view the sliding side (11) is in the fully lowered position resting on the mount (22) at the base of the slide rail (16). To move from the fully raised position shown in Figure 6a and the fully lowered position shown in Figure 7a, the sliding side (11) has been raised slightly to take the load off the slide rail (16). In addition, the button (13) has been pushed downwards which has in turn put downward force on the rod (14). This has caused the latch (15) to rotate about the pin (18) and clear of the slide rail (16). For clarity, a portion of the latch mechanism is enlarged in Figure 7b. The sliding side (11) can be raised back to the position shown in Figure 6 by lifting the sliding side upwards until the latch (3) is raised above the top end of the slide rail (16). The word 'comprising' and forms of the word 'comprising' as used in this description and in the claims does not limit the invention claimed to exclude any variants or additions. Modifications and improvements to the invention will be readily apparent to those skilled in the art. Such modifications and improvements are intended to be within the scope of this invention.