AU2021209316A1 - A window chain winder - Google Patents

Abstract

A WINDOW CHAIN WINDER ABSTRACT An extension-limit device for a window chain winder 100. The window chain winder 100 has a chain 400 that is retractably extendable to control an opening of a window, the chain 400 having an enlarged portion 420. The extension-limit device has a track portion 240 and a restrictor 300. The restrictor 300 has an arm portion. A restricted opening is defined between the arm portion and a wall portion of the chain-extension device or of the window chain winder for allowing a passage of the chain 400 for extension or retraction thereof and for trapping the enlarged portion 420 of the chain to limit an extension of the chain 400. The restrictor 300 is moveable along the track portion 240 to one of a plurality of locations along the track portion 240, each location corresponding to an allowed extension length of the chain 400. 1/4 100 120 440 4000 146 220 200 FIGURE 1A 10040 120 300 400 240 260 200 160220 420 140 FIGURE 1B

Description

1/4

100 120

440

146

4000 220 200 FIGURE 1A

10040

120 300 400 240 260

200 160220 420 140

FIGURE 1B

A WINDOW CHAIN WINDER

Field

[0001] The present invention relates to a window chain winder. Preferred embodiments of the invention relate to an extension-limit device for a chain winder for providing an adjustable extension limit of a chain from the chain winder.

Background

[0002] The current Building Code of Australia (BCA) standard requires bedroom windows above a certain height to be restricted to a maximum opening of about 125mm. In addition, the standard requires the windows to be able to maintain this opening while applying a predetermined force on the window. A purpose of this standard is to prevent a child from falling out from the window.

[0003] An existing window chain winder for restricting a window opening is mountable on a window frame and has a chain that is attached to a window that is pivotable relative to the window frame. The chain is windable to extend or retract the chain to thereby adjust the opening of the window. The existing winder restricts the chain up to a fixed length (e.g. 90mm), which would allow for the maximum opening of 125mm with respect to window frames of a certain size. The existing window chain winder is not usable across different window frames because different widths of the window frame and the fixed length of the chain would result in different maximum openings for the window. A larger frame width could result in an insufficient window opening thereby limiting airflow into the room, while a narrower frame width could result in a larger opening that does not comply with the BCA standard mentioned above.

Summary of Invention

[0004] Preferred embodiments of the present invention seek to address one or more of the problems discussed above and/or to at least provide the public with a useful choice.

[0005] An aspect of the present invention provides an extension-limit device for a window chain winder, the window chain winder having a chain that is retractably extendable to control an opening of a window, the chain having an enlarged portion, the extension-limit device including: a track portion; a restrictor having an arm portion, a restricted opening being defined between the arm portion and a wall portion of the chain-extension device or of the window chain winder for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain, wherein the restrictor is moveable along the track portion to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain.

[0006] The wall portion is preferably of the chain-extension device. In a preferred embodiment, the extension-limit device includes a base on which the track portion is provided, the base being engageable with a cover to define a housing in which the chain can be housed and from which the chain is retractably extendable. In this embodiment, the wall portion is of the base.

[0007] In other examples, the wall portion may be of the window chain winder. For example, window chain winder includes a housing from which the chain is retractably extendable, the wall portion being of the housing.

[0008] The track portion preferably provides bracing to the restrictor to prevent movement of the restrictor relative to the track portion during an extension of the chain. In an example, the track portion includes a sawtooth formation, and the restrictor includes a body portion from which the arm portion extends, the body portion having a sawtooth formation for complementarily engaging the sawtooth formation of the track portion.

[0009] The restrictor may include a track-follower portion that is engageable with the track portion, the track-follower portion having an aperture in which a fastener is fastenable for securing the restrictor to the track portion, the fastener being unfastenable from aperture to allow the restrictor to be moved along the track portion.

[0010] In an embodiment, the restrictor may include a second follower portion for engaging a guide portion in a housing of the window chain winder that houses the extension-limit device.

[0011] The track portion preferably includes: a first portion with which the restrictor is engageable to define the restricted opening between the arm portion and the wall portion for trapping the enlarged portion of the chain to limit an extension of the chain; and a second portion with which the restrictor is engageable to define an unrestricted opening between the arm portion and the wall portion for allowing passage of the chain and the enlarged portion of the chain, wherein a distance of the second portion to the wall portion is greater than a distance of the first portion to the wall portion.

[0012] Another aspect of the present invention provides a window chain winder for a window, the window chain winder including: a housing; a chain housed within the housing, the chain being retractably extendable from the housing to control an opening of the window, the chain having an enlarged portion; and the chain extension device of the aspect previously described above, the restrictor being selectively adjustable with respect to the track portion to limit an extension of the chain from the housing.

[0013] A further aspect of the present invention provides a window chain winder for a window, the window chain winder including: a housing defined by a wall portion and having a track portion, the housing for containing a chain that is retractably extendable from the housing to control an opening of the window, the chain having an enlarged portion; and a restrictor having an arm portion, a restricted opening being defined between the arm portion and the wall portion for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain, wherein the restrictor is moveable along the track portion to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain from the housing.

[0014] The window chain winder according to this aspect may further include the chain with the enlarged portion.

[0015] Yet a further aspect of the present invention provides a window chain winder for a window, the window chain winder including: a housing; a chain housed within the housing, the chain being retractably extendable from the housing to control an opening of the window; and a restrictor cooperable with the chain to limit an extension of the chain from the housing, the restrictor being selectively configurable to one of a plurality of configurations, each configuration corresponding to an allowed extension length of the chain from the housing.

[0016] The window chain winder preferably further includes a track portion along which the restrictor is moveable, the track portion being moveable to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain, the plurality of locations corresponding to the plurality of configurations.

[0017] The track portion may provide bracing to the restrictor to prevent movement of the restrictor relative to the track portion during an extension of the chain. In one example, the track portion includes a sawtooth formation, and the restrictor includes a body portion, the body portion having a sawtooth formation for complementarily engaging the sawtooth formation of the track portion.

[0018] The restrictor preferably includes a track-follower portion that is engageable with the track portion, the track-follower portion having an aperture in which a fastener is fastenable for securing the restrictor to the track portion, the fastener being unfastenable from the aperture to allow the restrictor to be moved along the track portion.

[0019] In a preferred embodiment, the restrictor has an arm portion, a restricted opening being defined between the arm portion and a wall portion of the housing for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain. The restrictor may be configurable to provide an unrestricted opening between the arm portion and the wall portion for allowing passage of the chain and the enlarged portion of the chain.

[0020] Preferably, the window chain winder further includes an adjustment feature that is coupled to the restrictor and that is accessible from an exterior of the housing, the adjustment feature being actuatable to cause an adjustment in a location or configuration of the restrictor. The adjustment feature may be a head of the fastener that is fastenable into the restrictor to secure the restrictor to the track portion. The adjustment feature is preferably accessible from a bottom wall of the housing and is concealed when the window chain winder is installed. For example, when the window adjustment device is mounted on a window frame, the bottom wall of the housing faces down on the window frame thereby concealing the adjustment feature. The housing may include a visual scale in proximity to the adjustment feature, the visual scale having a plurality of values, each value representing an allowed extension length of the chain, wherein the visual scale correlates a plurality of locations of the adjustment feature with respect to the scale to respective allowed extension lengths of the chain.

Brief Description of Drawings

[0021] Preferred embodiments of the invention will now be described, by way of non-limiting example, with reference to the accompanying drawings in which:

Figures 1A and 1B show perspective and top views respectively of the chain winder according to an embodiment of the present invention;

Figures 2A to 2C show perspective, sectional side and underside views respectively of a base for a chain winder according to an embodiment of the present invention;

Figures 3A and 3B show front perspective and end views respectively of a restrictor for a chain winder according to an embodiment of the present invention;

Figures 4A and 4B show perspective and side views respectively of an end stop of the chain for a chain winder according to an embodiment of the present invention;

Figure 5 shows a sectional end view of the chain winder with the restrictor housed therein according to an embodiment of the present invention;

Figures 6A to 6C show the chain winder with the restrictor in an unrestricted configuration;

Figures 7A to 7C show the chain winder with the restricted in a restricted configuration; and

Figures 8A to 8C show the chain winder with the restricted in another restricted configuration.

Description of Embodiments

[0022] Figures 1A and 1B schematically depict a window chain winder 100 according to an embodiment of the present invention. The window chain winder 100 includes a housing or a hollow body defined by a base 200 and a cover from which a handle 140 projects and from which a chain 400 is retractably extendable. The base includes an extension-limit device that is selectively adjustable by a user to provide a range of different extension limits for the chain 400. The extension-limit device includes a track portion and restrictor that will be described in further detail below. Figures 1A and lB show the window chain winder 100 with the cover removed, revealing the internal components of the window chain winder on the base 200.

[0023] The base 200 of the window chain winder 100 is securable to a window frame to which a window is pivotably coupled, the window chain winder being actuatable to control an opening on the window relative to the window frame. In a preferred example, the base 200 is mounted to a lower frame portion of the window frame. In other examples, the base 200 may be mounted to a side frame portion or an upper frame portion of the window frame.

[0024] The base 200 is a longitudinal member that includes a plurality of apertures, each through which a fastener is passable to secure the window chain winder to the window frame. The fastener may be a threaded fastener such as a screw for example. The base 200 abuts, or rests on, the window frame to which it is secured. That is, when the chain winder 100 is located on the window frame, the base 200 is face down on the window frame.

[0025] Located internally within the housing is a sprocket 160 that is rotatably driven about a sprocket axis by a pinion gear 120 to which a handle 140 is attached. The sprocket 160 is rotatably mounted on the base 200. The handle 140 is actuatable by a user (i.e., windable by the user) to cause the pinion gear 120 to rotate thereby causing the sprocket 160 to also rotate. The sprocket 160 is rotatable in a first direction (upon rotation of the handle 140) or in a second direction (upon counter-rotation of the handle 140). The sprocket 160 is located near or adjacent to an opening through which the chain 400 retractably extends. Once the window chain winder 100 is installed, the handle 140 can be operated to cause the chain 400 to project a desired amount from the housing, up to the maximum allowable extension limit as defined by a restrictor 300, which will be described in further detail below. The handle can also be operated to retract the extended chain back into the housing.

[0026] The housing has an opening through which the chain 400 retractably extends. The chain 400 includes a plurality of pivotally attached links, with adjacent links being pivotally attached to each other by a pin. At one (first) end of the chain 400, there is provided a mounting portion 440 for mounting to the window, e.g. a sash of the window. At another (second) end of the chain, there is provided an enlarged portion or an abutment 420 that is cooperable with an adjustable restrictor 300, which will be described in further detail below, for limiting an extension of the chain 400 from the housing. In particular, the enlarged portion 420 is abuttable against the restrictor 300. In normal installed configuration of the window chain winder 100, the first end of the chain 400 to which the mounting portion 440 is provided is always externally located from the housing of the window chain winder, while the second end of the chain to which the enlarged portion 420 is provided is internally located in the housing. A portion of the chain 400 within the housing is located in a generally flat plane, with the enlarged portion 420 extending generally normal relative to that plane. Accordingly, the enlarged portion 420 extends generally normal to that chain portion.

[0027] The chain 400 is engaged by the sprocket 160 such that the sprocket 160 drives the chain 400 to retractably extend the chain 400 with respect to the housing. In particular, the sprocket 160 drives the chain 400 between an extended position with at least a portion of the chain 400 extending from the housing and a retracted position in which at least a majority of the chain 400 is located internally of the housing. For example, rotation of the sprocket 160 in a first direction (caused by rotation of the handle 140) drives the chain 400 to extend from the housing to the extended position and rotation of the sprocket 160 in a second direction (caused by a counter rotation of the handle 140) drives the chain to retract into the housing to the retracted position.

[0028] The base 200 has a wall portion (or a floor portion) 220 along with the chain 400 and/or the enlarged portion 420 is slidable upon rotation of the sprocket 160. The floor portion 220 is a longitudinal and substantially flat member having a length and a width.

[0029] The base 200 has a track portion 240. The track portion 240 has a track length that extends along a track axis that is parallel to a longitudinal axis along which the length of the wall portion 220 extends. The track portion 240 extends upwardly from the wall portion 220. The track portion 240 is located near an end of the base 200 opposite to the end at which the opening of the housing is provided through which the chain 400 retractably extends. The track portion 240 is located substantially centrally, widthwise, relative to wall floor portion 220.

[0030] The base 200 has a guide portion 260 at an end opposite to where the opening in the housing, through which the chain 400 is retractably extendable, is provided. The guide portion 260 extends upwardly from the wall portion 220. There is a clearance between an end of the track portion 240 and the guide portion 260 for a passage of the chain 400 and the enlarged portion 420. The track portion 240 is between the opening through which the chain 400 retractably extends and the guide portion 260. The guide portion 260 has a U- or curved shape. During a retraction or extension of the chain 400, the chain 400 follows a path in the housing that includes two laterally-spaced apart linear path portions and joined by an end 'U' (or curved) path portion, the 'U' path portion being defined by the curvature of the guide portion 260. The track portion 240 separates the two linear path portions such that, during retraction or extension, the chain 400 progresses along one of the linear path portions on one side of the track portion

240, along the curved path portion around an end of the track portion 240 as guided by the guide portion 260, and along the other linear path portion on the other side of the track portion 240.

[0031] The window chain winder 100 includes a restrictor 300 that is cooperable with the chain 400 to limit an extension of the chain 400 from the housing, the restrictor 300 being selectively configurable to one of a plurality of configurations, each configuration corresponding to an allowed extension length of the chain 400 from the housing. The restrictor 300 is captively located within the housing. The restrictor 300 is engageable with the track portion 240, and moveable along a length of the track portion 240 to one of a plurality of locations on the track portion, each location corresponding to a respective configuration of the restrictor 300 that defines a corresponding allowed extension length of the chain. In particular, the restrictor 300 has an arm portion such that, when the restrictor is located on the track portion 240, a restricted opening or gate is defined between the arm portion and the wall portion 220 of the base 200 through which a passage of the chain is allowed for extension or retraction thereof. A height of the restricted opening is smaller than a height of the enlarged portion 420 such that passage of the enlarged portion 420 of the chain 420 past the restrictor would be stopped by the arm portion thereby limiting an extension of the chain 400 from the housing.

[0032] The window chain winder 100 further includes a locking arrangement 180 with a keyhole that is accessible from an exterior of the housing. A key is interactable with the locking arrangement 180 via the keyhole to cause the locking arrangement 180 to assume a locked configuration in which the locking arrangement 180 traps the chain 400 relative to the housing to restrict movement of the chain 400 relative to the housing or an unlocked configuration in which the locking arrangement 180 releases the chain 400 relative to the housing to allow a retractable extension of the chain 400 relative to the housing.

[0033] Figures 2A to 2C show the base 200, which includes the wall (or floor) portion 220, track portion 240, and guide portion 260 as previously described above.

[0034] With reference to Figures 2A and 2B, the track portion 240 includes a pair of laterally spaced apart upright walls on opposite sides of a slot in the base 220. The track portion 240 includes sawtooth formation. The sawtooth formation is formed at an upper region or surface of each upright wall of the track portion 240. The sawtooth formation of the track portion 240 is complementarily engageable with a sawtooth formation of the restrictor. The sawtooth formation defines a plurality of discrete locations for the restrictor relative to the track portion 240, each discrete location corresponding to a respective allowed extension limit for the chain from the housing. The sawtooth formation also provides some bracing to the restrictor to prevent movement of the restrictor relative to the track portion during an extension of the chain particularly when the enlarged portion abuts the restrictor and the user attempts to continue to wind the handle to further extend the chain. Thereby, the sawtooth formation resists a movement of the restrictor that may be caused by drawing the enlarged portion against it. In particular, the sawtooth formation is formed by a plurality of sloped portions and a plurality of upright portions, each upright portion connecting one end of a sloped portion with an end of an adjacent sloped portion. Each sloped portion is sloped upwardly away from the opening through which the chain is retractably extendable. The upright portions provide bracing to the restrictor.

[0035] The track portion 240 includes a first portion 242 and a second portion 244. A height or distance of the second portion 244 relative to the wall (floor) portion 220 is greater than a height or distance of the first portion 242 relative to the wall (floor) portion 220. When the restrictor is engaged with the first (lower) portion 242, the restricted opening as previously described is defined for trapping the enlarged portion of the chain to limit an extension thereof. When the restrictor is engaged with the second (higher) portion 244, an unrestricted opening is defined between the arm portion and the wall portion for allowing passage of the chain and the enlarged portion of the chain. Thereby, the user is able to configure the window chain winder in a restricted configuration in which the user can set one of a plurality of allowable extension limits for the chain from the housing or an unrestricted configuration in which a maximum and unrestricted extension of the chain from the housing would be allowed.

[0036] With reference to Figure 2C, an underside of the base 220 includes a slot 222. The pair of spaced apart upright walls of the track portion previously described are on opposite sides of this slot 222. A fastener, which passes from the underside of the base, is engageable with the restrictor via the slot 222. Thereby, the fastener is fastenable to secure or clamp the restrictor onto the track portion thereby preventing longitudinal movement of the restrictor relative to the track portion. The fastener can be unfastened, without completely removing the fastener from the restrictor, to allow the restrictor to be adjusted longitudinally along track portion, that is anywhere along the length of the first portion of the track portion to define the restricted opening for the track portion or the second portion of the track portion to define the unrestricted opening for the track portion as previously described. In particular, while the fastener is unfastened but still engaged with the restrictor, the user can drag the head of the fastener along the slot, which would move the restrictor in unison with the fastener, to thereby adjust the location of the restrictor relative to the track portion and adjust the extension limit for the chain.

[0037] The base 220 includes a visual scale adjacent the slot 222 that correlates different locations of the fastener in relation to the slot each to a respective extension limit for the chain. Thereby, the user would be able easily set a desired extension limit for the chain by dragging the fastener head to a particular location of the slot based on the visual scale. The fastener head is an adjustment feature that is accessible from an exterior of the housing and that is actuatable by a user to adjust the location of the restrictor with respect to the track portion. The adjustment feature is concealed when the window chain winder is installed. The visual scale has a range of values in 5mm increments with a minimum value on the scale being 90mm and a maximum value on the scale being 150mm. These values correspond to the allowable extension limits of the chain from the housing when the restrictor is engaged with the track portion anywhere along the first (lower) portion thereof. The visual scale also includes a location at an end of the slot marked 'UNR' corresponding to a location at which the restrictor would be engaged with the second (higher) portion of the track portion to define the unrestricted opening to provide unrestricted extension of the chain from the housing. In other examples, the visual scale may have increments smaller or larger than 5mm between adjacent values (e.g. increments of1mm, 2mm, or 10mm). In yet other examples, the minimum and maximum values of the scale may also be different.

[0038] Once the chain winder 100 is installed on the window frame, the fastener that fastens into the restrictor through the slot 222 via the underside of the base 220 becomes inaccessible. In particular, the head of the fastener is concealed on an underside of the chain winder 100. Thus according to this embodiment - the chain extension limit of the window chain device once the window chain device is secured to the window frame cannot be adjusted. To adjust the chain extension limit, the window chain device would need to be unsecured from the window frame so that a user can access the fastener to thereby adjust the restrictor to allow for a desired chain extension limit. Thereafter, the window chain winder can be resecured to the window frame. This feature prevents any tampering of the window adjustment device to increase the opening beyond the requirements of the Building Code of Australia (BCA) standard as described in the Background section.

[0039] Figures 3A and 3B show the restrictor 300 as previously described above. The restrictor 300 includes a body portion 320, the arm portion 340, a foot portion 360, and a head portion 380. The arm portion 340 extends laterally from the body portion 320 while the foot portion 360 and head portion 380 extends vertically in mutually opposite directions from the body portion 320.

[0040] The body portion 320 of the restrictor 300 has a sawtooth formation 322 on an underside thereof for complementarily engaging the sawtooth formation of the track portion. The sawtooth formations in the restrictor and track portion define a plurality of discrete locations for the restrictor 300 on the track portion, each discrete location corresponding to a respective allowable extension limit for the chain. In the example shown, the sawtooth formation 322 of the body portion 320 has a plurality of teeth for engaging the teeth of the track portion. In another example, the body has one tooth portion for engaging the track portion. In yet another example, the track portion and restrictor may be engageable with each other via some other means that allows for either a plurality of discrete locations for the restrictor relative to the track portion or a continuous (non-discrete) range of locations of the restrictor relative to the track portion.

[0041] The arm portion 340 of the restrictor extends laterally from the body portion 320. The arm portion 340 defines, with a wall portion of the base, the restricted opening for trapping the enlarged portion of the chain thereby limiting the extension of the chain from the housing. In particular, the enlarged portion is abuttable against a surface of the arm portion to restrict a further extension of the chain. The surface of the arm portion against which the enlarged portion is abuttable is slopped.

[0042] The foot portion 360 of the restrictor 300 is locatable in between the upright wall portions of the track portion of the base as previously described above. The fastener is fastenable via the underside of the base into the foot portion 340 to secure the restrictor relative to the track portion. The foot portion includes an aperture on an underside thereof into which the fastener is fastenable. The foot portion 360 is a track-follower portion that is engageable with the track portion.

[0043] The head portion 380 of the restrictor 300 is locatable in a channel of the cover of the housing. The channel in the cover acts as an additional guide for guiding a linear movement of the restrictor relative to the track portion. The head portion is another follower portion, in addition to the follower portion formed by the foot portion 360, for engaging the channel.

[0044] When the housing is assembled, the restrictor 300 is trapped longitudinally with respect to the track portion and prevented from any lateral (side-to-side) movement relative to the track portion. In particular, the restrictor 300 is trapped via a first (lower) engagement of the foot portion 360 between the upright walls of the track portion and via a second (upper) engagement of the head portion 380 with the channel in the cover. Some vertical movement of the restrictor with respect to the housing would be permitted to allow for the restrictor to be adjusted longitudinally along the track portion. If the fastener is completely removed from the foot portion 360, the restrictor 300 would remain trapped longitudinally in the housing with respect to the track portion such that the user would be able to easily refasten a fastener into the restrictor without having to remove the cover to realign the restrictor on the track portion.

[0045] Figures 4A and 4B show the enlarged portion 420 that is attached to the second end of the chain as previously described above, the enlarged portion has a tongue portion 422 with an aperture. The last link of the chain receives the tongue portion 422 and a pin skewers the last link of the chain and the tongue portion via the aperture in the tongue portion such that the enlarged portion is pivotable relative to the last link of the chain. The enlarged portion 420 has a head portion 424 from which the tongue portion 422 extends. The head portion 420 has a height that is greater than a height of the restricted opening defined between the restrictor and the wall portion previously described above such that the head portion 420 would be trapped behind the restrictor thereby limiting an extension of the chain from the housing. The head portion has an inwardly sloped wall that is abuttable against the sloped surface of the arm portion of the restrictor as previously described above. The slopped contact surfaces of the enlarged portion and of the arm portion of the restrictor provide a positive engagement between the enlarged portion and the arm portion. In particular, the inwardly sloped wall of the enlarged portion defines a space in which the slopped surface of the arm portion is locatable to thereby restrict further movement of the enlarged portion towards the arm portion.

[0046] The enlarged portion 420 has an inwardly curved profile in that there is a slight/subtle curvature on one side of the enlarged portion the body from the head portion 424 to the tongue portion 422. This slight/subtle curvature facilitates the progression of the enlarge portion 420 around the track portion (in the space between the end of the track portion and the guide portion) while not disrupting the progression of the chain when the enlarged portion is at either of the linear path portions previously described.

[0047] Figure 5 shows a sectional view of the window chain winder 100 according to an embodiment of the present invention, with the chain removed. The window chain winder 100 has a housing defined by the cover 110 and the base 200. The cover is removable from the base to reveal the internal componentry of the window chain winder as previously described above.

[0048] The pair of laterally-spaced apart upright walls of the track portion 240 extends upwardly from the wall portion 220 of the base and receives therebetween the foot portion 360 of the restrictor 300. The base 200 has a recessed portion on an underside thereof leading to the slot 222. The fastener 500 is fastenable into the foot portion 360 of the restrictor 360 via the slot 222. When fastened into the foot portion 360, the head of the fastener 500 is wholly within the recessed area and does not protrude therefrom such that the base can be stably located on the window frame. That is, when fastened, the head of the fastener 500 is concealed or hidden and does not bulge or protrude from the base 200. The fastener 500 can be unfastened to allow the restrictor 300 to be slid backwards or forwards along the track portion 240 to adjust the allowable extension limit for the chain, as previously described above, by dragging a head of the fastener along the slot 222 which causes the restrictor 300 to move in unison with the fastener 500. Once at the desired location, the fastener 500 is fastened into the foot portion 360 to thereby secure the position of the restrictor 300 relative to the track portion 240.

[0049] An upper wall of the cover 110 has a channel defined by a pair of laterally spaced apart channel wall portions 112 extending along a length of the cover. The wall of the cover 110 on which the channel wall portions 112 are provided is an internal wall portion of the housing. The head portion 380 of the restrictor is locatable in the channel defined by the channel wall portions 112 such that the channel in the cover acts as an additional guide for guiding a linear movement of the restrictor relative to the track portion, as previously described above. In addition, as previously described above, when assembled, the restrictor 300 is trapped longitudinally with respect to the track portion 240 and prevented from any lateral (side-to-side) movement relative to the track portion 240 via the first (lower) engagement of the foot portion 360 between the upright walls of the track portion 240 and via a second (upper) engagement of the head portion 380 between the channel wall portions 112 in the cover. Some vertical movement of the restrictor with respect to the housing would be permitted to allow for the restrictor to be adjusted longitudinally along the track portion.

[0050] The arm portion 340 defines, with the wall portion 220 of the base 200, the restricted opening for trapping the enlarged portion of the chain thereby limiting the extension of the chain from the housing. The location of the restricted opening can be adjusted longitudinally forwardly or rearwardly along the track portion by adjusting the location of the restrictor 300 relative to the track portion 24 as previously described, thereby providing an adjustability in the allowable extension limit for the chain.

[0051] Figures 6A to 6C, 7A to 7C, and 8A to 8C show different configurations of the restrictor of the window chain winder according to a preferred embodiment of the present invention.

[0052] Figures 6A to 6C show the window chain winder 100 when the restrictor 300 is on the second (higher) portion of the track portion 240 to thereby provide the unrestricted opening between the arm portion of the restrictor 300 and the wall portion 220 of the base. As shown in Figure 6C, the fastener 500 is at the end of the slot in the base that is marked as UNR according to the visual scale on the underside of the base. In this restrictor configuration, the chain is free to move unrestrictedly relative to the housing to its maximum chain length from the housing.

[0053] Figures 7A to 7C show the window chain winder 100 when the restrictor 300 is at a location on the first (lower) portion of the track portion 240 to thereby provide a restricted opening between the arm portion of the restrictor 300 and the wall portion 220 of the base. As shown in Figure 7C, the fastener 500 is located at the slot in the base that is marked as '150' according to the visual scale on the underside of the base. In this restrictor configuration, the chain is free to move up to 150mm from the housing.

[0054] Figures 8A to 8C show the window chain winder 100 when the restrictor 300 is at another location on the first (lower) portion of the track portion 240 to thereby provide a restricted opening between the arm portion of the restrictor 300 and the wall portion 220 of the base. As shown in Figure 8C, the fastener 500 is located at the slot in the base that is marked as '90' according to the visual scale on the underside of the base. In this restrictor configuration, the chain is free to move up to 90mm from the housing.

[0055] Preferred embodiments of the present invention therefore provide a window chain winder 100 with a variable restrictor that can restrict the chain in increments (e.g. 5mm increments) between 90 and 150mm. In addition, the window chain winder 100 provides an unrestricted configuration in which the restrictor is elevated from the base to allow the chain to move uninterruptedly pass the restrictor. The restrictor and track portion have teeth formations that are complementarily engageable with each other to provide the discrete and incremental adjustment of the restrictor relative to the track portion. The adjustment is achieved by unfastening the fastener from an underside of the base and sliding the fastener to a required location along the slot which moves the restrictor in unison with the fastener. The fastener is then refastened into the restrictor to secure the restrictor to the track portion.

[0056] The various embodiments of the present invention described above have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. The present invention should not be limited by any of the exemplary embodiments described above.

Claims (19)

1. An extension-limit device for a window chain winder, the window chain winder having a chain that is retractably extendable to control an opening of a window, the chain having an enlarged portion, the extension-limit device including: a track portion; a restrictor having an arm portion, a restricted opening being defined between the arm portion and a wall portion of the chain-extension device or of the window chain winder for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain, wherein the restrictor is moveable along the track portion to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain.

2. The extension-limit device of claim 1, wherein the wall portion is of the chain-extension device.

3. The extension-limit device of claim 1 or 2, wherein the track portion provides bracing to the restrictor to prevent movement of the restrictor relative to the track portion during an extension of the chain.

4. The extension-limit device of any one claims I to 3, wherein the track portion includes a sawtooth formation, and the restrictor includes a body portion from which the arm portion extends, the body portion having a sawtooth formation for complementarily engaging the sawtooth formation of the track portion.

5. The extension-limit device of any one of claims 1 to 4, wherein the restrictor includes a track-follower portion that is engageable with the track portion, the track-follower portion having an aperture in which a fastener is fastenable for securing the restrictor to the track portion, the fastener being unfastenable from the aperture to allow the restrictor to be moved along the track portion.

6. The extension-limit device of any one of claims 1 to 5, wherein the restrictor includes a second follower portion for engaging a guide portion in a housing of the window chain winder that houses the extension-limit device.

7. The extension-limit device of any one of claims 1 to 6, wherein the track portion includes: a first portion with which the restrictor is engageable to define the restricted opening between the arm portion and the wall portion for trapping the enlarged portion of the chain to limit an extension of the chain; and a second portion with which the restrictor is engageable to define an unrestricted opening between the arm portion and the wall portion for allowing passage of the chain and the enlarged portion of the chain, wherein a distance of the second portion to the wall portion is greater than a distance of the first portion to the wall portion.

8. A window chain winder for a window, the window chain winder including: a housing; a chain housed within the housing, the chain being retractably extendable from the housing to control an opening of the window, the chain having an enlarged portion; and the chain extension device of any one of claims 1 to 7, the restrictor being selectively adjustable with respect to the track portion to limit an extension of the chain from the housing.

9. A window chain winder for a window, the window chain winder including: a housing defined by a wall portion and having a track portion, the housing for containing a chain that is retractably extendable from the housing to control an opening of the window, the chain having an enlarged portion; and a restrictor having an arm portion, a restricted opening being defined between the arm portion and the wall portion for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain, wherein the restrictor is moveable along the track portion to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain from the housing.

10. A window chain winder for a window, the window chain winder including: a housing; a chain housed within the housing, the chain being retractably extendable from the housing to control an opening of the window; and a restrictor cooperable with the chain to limit an extension of the chain from the housing, the restrictor being selectively configurable to one of a plurality of configurations, each configuration corresponding to an allowed extension length of the chain from the housing.

11. The window chain winder of claim 10, further including a track portion along which the restrictor is moveable, the track portion being moveable to one of a plurality of locations along the track portion, each location corresponding to an allowed extension length of the chain, the plurality of locations corresponding to the plurality of configurations.

12. The window chain winder of claim 11, wherein the track portion provides bracing to the restrictor to prevent movement of the restrictor relative to the track portion during an extension of the chain.

13. The window chain winder of claim 11 or 12, wherein the track portion includes a sawtooth formation, and the restrictor includes a body portion, the body portion having a sawtooth formation for complementarily engaging the sawtooth formation of the track portion.

14. The window chain winder of any one of claims 11 to 13, wherein the restrictor includes a track-follower portion that is engageable with the track portion, the track-follower portion having an aperture in which a fastener is fastenable for securing the restrictor to the track portion, the fastener being unfastenable from aperture to allow the restrictor to be moved along the track portion.

15. The window chain winder of any one of claims 10 to 14, wherein the restrictor has an arm portion, a restricted opening being defined between the arm portion and a wall portion of the housing for allowing a passage of the chain for extension or retraction thereof and for trapping the enlarged portion of the chain to limit an extension of the chain.

16. The window chain winder of claim 15, wherein the restrictor is configurable to provide an unrestricted opening between the arm portion and the wall portion for allowing passage of the chain and the enlarged portion of the chain.

17. The window chain winder of any one of claims 8 to 16, further including an adjustment feature that is coupled to the restrictor and that is accessible from an exterior of the housing, the adjustment feature being actuatable to cause an adjustment in a location or configuration of the restrictor.

18. The window chain winder of claim 17, wherein the adjustment feature is accessible from a bottom wall of the housing and, when the window adjustment device is mounted on a window frame, the bottom wall of the housing faces down on the window frame thereby concealing the adjustment feature.

19. The window chain winder of claim 17 or 18, wherein the housing includes a visual scale in proximity to the adjustment feature, the visual scale having a plurality of values, each value representing an allowed extension length of the chain, wherein the visual scale correlates a plurality of locations of the adjustment feature with respect to the scale to respective allowed extension lengths of the chain.

Alchin Long Group IP Pty Limited

Patent Attorneys for the Applicant/Nominated Person

SPRUSON&FERGUSON