WO2012031716A2

WO2012031716A2 - Blind assembly

Info

Publication number: WO2012031716A2
Application number: PCT/EP2011/004403
Authority: WO
Inventors: Nicolaas Dekker; Paul Joost Bram Wensink; Hervé Lepetit
Original assignee: Hunter Douglas Industries BV
Current assignee: Hunter Douglas Industries BV
Priority date: 2010-09-06
Filing date: 2011-08-31
Publication date: 2012-03-15
Anticipated expiration: 2013-03-06
Also published as: DE212011100139U1; WO2012031716A3

Abstract

A headrail assembly for a blind assembly, comprising: a tubular body from which the slats of the blind assembly are to be suspended; a control assembly comprising an attachment part by which the tubular body is to be attached to the fixed world, a housing that is fixed relative to the attachment part, a tilt control mechanism, associated with the housing, comprising a tilt control member via which a user-applied torque is transmitted to the tilt control mechanism and a body connector coupled between the tilt control mechanism and the tubular body, and a lift cord control mechanism, associated with the housing, comprising lift cords; wherein the lift cords are routed so as to pass from the lift cord control mechanism, through the housing and into the tubular body via a hollow fixed shaft, forming part of the housing, about which the body connector and the tubular body are arranged to rotate in unison when the body connector is subjected to torque transmitted from the tilt control member.

Description

BLIND ASSEMBLY

The present invention relates to a headrail assembly for a blind assembly and to a blind assembly per se.

Venetian blinds comprise a headrail by which the blinds are connected to a window or door frame. The headrail includes the control mechanisms by which the slats are tilted and the blinds are raised and lowered. The headrail may be a stationary structure or a rotary structure. A typical example of a Venetian blind with a generally cylindrical rotary headrail is shown in US3605852. This Venetian blind has the tilt control mechanism at one end and the lift cord control mechanism at the other end. The tilt control mechanism comprises a worm drive in which the worm is rotated by tilt cords to drive a tilter gear the output shaft of which transmits torque to the rotary headrail for its rotation. The worm drive is popularly used as part of a tilt control mechanism since it, by its nature, retains the headrail at the selected desired angle even under the weight of the slats. The present invention is generally concerned with providing an

alternative to the above-mentioned conventional arrangement.

According to a first aspect, the present invention may provide a headrail assembly for a blind assembly, comprising: a tubular body from which the slats of the blind assembly are to be suspended; a control assembly comprising an attachment part by which

the tubular body is to be attached to the fixed world, a housing that is fixed relative to the attachment part, a tilt control mechanism, associated with the housing, comprising a tilt control member via which a user- applied torque is transmitted to the tilt control mechanism and a body connector coupled between the tilt control mechanism and the tubular body, and a lift cord control mechanism, associated with the housing, comprising lift cords; wherein the lift cords are routed so as to pass from the lift cord control mechanism, through the housing and into the tubular body via a hollow fixed shaft, forming part of the housing, about which the body connector and the tubular body are arranged to rotate in unison when the body connector is subjected to torque transmitted from the tilt control member. In the headrail assembly of the first aspect of the present invention the component that transmits the output torque of the tilt control mechanism, namely, the body connector, rotates about a fixed hollow shaft via which the lift cords are delivered from the lift cord control mechanism to the tubular body of the headrail assembly. This structure, which is not present in the prior art, provides the building block upon which the preferred embodiments featured in the accompanying drawings are based.

Preferably, the tubular body is generally slat shaped. Making the tubular body generally slat shaped enables it, unlike a cylindrical body, also to perform the role of a regular slat in selectively blocking the passage of light.

According to a second aspect, the present invention may provide a blind assembly comprising a headrail assembly according to the first aspect of the present invention, and a plurality of slats suspended from the headrail assembly, and a plurality of ladder sets connected to the body and the slats such that rotation of the body causes a corresponding tilting motion in the slats. According to a third aspect, the present invention may provide a headrail assembly for a blind assembly, comprising: a tubular body from which the slats of the blind assembly are to be suspended; a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a housing having a first shaft that is fixed relative to the attachment part, a tilt control

mechanism, associated with the housing, and comprising a tilt

control member by which the tilt control mechanism is controlled, and a body connector coupled between the tilt control mechanism and the tubular body; wherein the tilt control mechanism comprises a rotation amplification device coupled between the tilt control member and the body

connector that is constructed to translate a unit rotation of the tilt control member into a larger corresponding rotation of the body connector. A headrail assembly according to the third aspect of the present invention has a control assembly which amplifies a rotational movement applied by the user into a greater rotation of the tubular body.

Preferably, the tubular body is generally slat shaped. Making the tubular body slat shaped enables it, unlike a cylindrical body, also to perform the role of a regular slat in selectively blocking the passage of light. In such a case, the rotational amplifying effect of the control assembly permits the slat-shaped tubular body to be driven between its near vertical inclined extremes while lessening the required corresponding motion of the tilt control member. Lessening the required motion of the tilt control member is advantageous in increasing design freedom for designs in which there is no interference between the tilt control member and the slat- shaped tubular body or the fixed world. Preferably, the headrail assembly further comprises an indexing

mechanism which provides tactile feedback to the user during operation of the tilt control mechanism. In one embodiment, the indexing mechanism is constructed to hold the tubular body in a rest position. Preferably, the headrail assembly further comprises a wrapped spring assembly coupled to the tilt control member and operable to allow the rotation of the tubular body when the tilt control member is rotated and to hold the tubular body rotationally immobile when the tilt control member is at rest.

According to a fourth aspect, the present invention may provide a blind assembly comprising a headrail assembly according to the third aspect of the present invention, and a plurality of slats suspended from the headrail assembly, and a plurality of ladder sets connected to the body and the slats such that rotation of the body causes a corresponding tilting motion in the slats.

According to a fifth aspect, the present invention may provide a headrail assembly for a blind assembly, comprising: a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a housing having a first shaft that is fixed relative to the attachment part, a wrapped spring assembly mounted to the first shaft, a tilt control member coupled to the wrapped spring assembly for transmitting a user-applied torque to the wrapped spring assembly; and a tubular body, from which slats of the blind assembly are to be

suspended, arranged to rotate in unison with the wrapped spring

assembly; wherein the control assembly is constructed such that, responsive to a user-applied torque from the tilt control member, the wrapped

spring assembly is released from a gripping condition in which it and the tubular body are held rotationally immobile with respect to the fixed shaft to a rotating condition in which it and the tubular body rotate in unison with respect to the fixed shaft. The control assembly of the fifth aspect of the present invention uses the above-defined wrapped spring assembly as a means of rotating the tubular body when the inclination of the slats is to be adjusted and a means of holding the tubular body rotationally immobile when the desired

inclination of the slats is reached.

Preferably, when the user-applied torque ceases the wrapped spring assembly returns to the gripping condition in which it is rotationally immobile.

Preferably, the tilt control member comprises a lever mounted for rotation about the first shaft. Preferably, the control assembly comprises a control wand connected to an end of the lever remote from the first shaft by which the user applies said torque to the wrapped spring assembly.

Preferably, the tilt control member comprises a gear wheel portion mounted for rotation about the first shaft and the wrapped spring assembly comprises a spring wrapped around the first shaft and an actuator member having a gear wheel portion and a finger

portion for interacting with the spring.

In a preferred embodiment, the control assembly comprises an

intermediate gear assembly operatively connected between the gear wheel portion of the tilt control member and the gear wheel portion of the actuator member and constructed to translate a unit rotation of the gear wheel portion of the tilt control member into a larger corresponding rotation of the gear wheel portion of the actuating member. The ratio of angular rotations may be 1 : 1.2 to 1.5, preferably 1.4. The intermediate gear assembly serves to amplify a rotational movement directly applied by the user through the control wand into a greater rotation of the tubular body. In this way, in embodiments where the slats must be capable of almost 180° rotation (between both almost vertical inclinations of the slats), the corresponding rotation which must be brought about in the tilt control member is correspondingly less and, as a consequence, the control wand need not approach the surrounding door or window frame. The use of the intermediate gear assembly in converting a unit rotation of the tilt control member into a greater rotation of the body enables the point at which the connection to the control wand takes place to fall within the cross-sectional profile of the control assembly without collision between the proximal end of the control wand and the body or the top cross-beam of the door/ window frame even when the slats (and the body when slat shaped) reach a light-minimising, almost vertical

inclination.

According to a sixth aspect, the present invention may provide a blind assembly comprising a headrail assembly according to a fifth aspect of the present invention, and a plurality of slats suspended from the headrail assembly, and a plurality of ladder sets connected to the body and the slats such that rotation of the body causes a corresponding tilting motion in the slats.

According to a seventh aspect, the present invention may provide a headrail assembly for a blind assembly, comprising: a tubular body, comprising a first body portion and a second body portion, from which the slats of the blind assembly are to be suspended; a support assembly comprising an attachment part for attaching the headrail assembly to the fixed world, a hollow tube fixedly coupled to the attachment part, first and second body connectors mounted for rotation about first and second ends of the hollow tube respectively and coupled to the first and second body portions respectively to rotate in unison

therewith, and a bracket, coupling the first and second body connectors, for transmitting torque from one of said body connectors to the other of said body connectors; a control assembly comprising a lift cord control mechanism via which lifts cords are routed into the tubular body; wherein a said lift cord is routed from one of said body portions to the other of said body portions through the hollow tube.

According to an eighth aspect, the present invention may provide a blind assembly comprising a headrail assembly according to the seventh aspect of the present invention, and a plurality of slats suspended from the headrail assembly, and a plurality of ladder sets connected to the body and the slats such that rotation of the body causes a tilting motion in the slats.

According to another aspect, the present invention may provide a head rail assembly for a blind assembly, comprising:

a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a housing having a first shaft that is fixed relative to the attachment part, a body connector rotatably mounted on the first shaft and for connection to a tubular body, from which slats of the blind assembly are to be suspended, arranged to rotate in unison with the body connector, a tilt control member coupled to the body connector for transmitting a user-applied torque to the body connector; and

wherein the first shaft and the body connector together form a detent arrangement for releasably holding the first shaft and the body connector in at least one predetermined relative rotational orientation.

Further subsidiary features of the present invention may be found in the appended claims and in the following description. Exemplary embodiments of the present invention are hereinafter described with reference to the accompanying drawings, in which:

Figure 1 shows a first Venetian blind assembly; Figures 2(a-c) show an exploded view, a view in cross-section, and a perspective view respectively of the connection of a ladder set to a portion of the body of the headrail assembly; Figure 3 shows an exploded view of a left-hand portion of the blind assembly shown in Figure 1 with some parts omitted;

Figure 4 shows a perspective view of a side control assembly with some parts omitted;

Figure 5 shows a view from the side of the side control assembly of Figure 4 with some parts omitted;

Figures 6(a-b) show an exploded view and a perspective view respectively of the side control assembly of Figures 4 and 5 with some parts omitted;

Figures 7(a-b) show an exploded view and a perspective view respectively of the intermediate and end support assemblies shown in Figure 1 ; Figures 8(a-b) show various views of an alternative embodiment with parts omitted;

Figure 9 shows an exploded view of the side control assembly of an alternative embodiment;

Figure 10 shows schematically an end view of the side control assembly of Figure 9;

Figure 1 1 shows a perspective view of the side control assembly of Figure 9;

Figures 12A, 12B and 12C show schematically an end view of the side control assembly of Figure 9 in three respective orientations; Figure 13 shows a view from the side of the side control assembly of Figures 4 to 6 with parts omitted which illustrates the routing of the lift cords;

Figure 14 shows a view of a horizontal cross-section through the head rail assembly which illustrates the routing of the lift cords;

Figure 15 shows a view from behind of a vertical cross-section of a part of the first blind assembly of Figure 1 which illustrates the routing of the lifting cords;

Figure 16 shows a view from behind a vertical cross-section of of a further part of the first blind assembly of Figure 1 which illustrates the routing of the lifting cords;

Figure 17 shows a second Venetian blind assembly;

Figures 18(a-b) show an exploded view and a perspective view respectively of the end support assembly of Figure 17; and

Figure 19 shows a view from behind a vertical cross-section of a part of the second blind assembly of Figure 17 which illustrates the routing of the lifting cords.

Throughout this description the same or corresponding parts have been given the same or corresponding reference numerals.

A first Venetian blind assembly 10 is shown in Figure 1. The blind assembly 10 comprises a headrail assembly 12 which is secured to the fixed world, for example, a door or window frame (not shown) by a side control assembly 14 spaced slightly inwardly from the left end of the headrail assembly 12, an intermediate support assembly 15 disposed midway along the headrail assembly 12 and a end support assembly 16 spaced inwardly from the right end of the headrail assembly 12. The headrail assembly 12 further comprises a tubular body, generally

designated 18, made up of a first tubular body portion 18a disposed from the left end of the headrail assembly 12 to the side control assembly 14; a second tubular body portion 18b disposed between the side control assembly 14 and the intermediate support assembly 15; a third tubular body portion 18c disposed between the intermediate support assembly 15 and the end support assembly 16; and a fourth tubular body portion 18d disposed between the end support assembly 16 and the right end of the headrail assembly 12.

The blind assembly 10 comprises a plurality of wooden slats 22 and a foot rail 23 that are held suspended in a generally horizontal orientation, and in parallel and spaced relation with one another by four ladder sets 20a-d which are arranged at spaced intervals along the length of the blind assembly 10. Each ladder set, comprises an inner ladder tape and an outer ladder tape, and extends from the headrail assembly 12 to the foot rail 23. Each slat 22 comprises four apertures disposed at spaced intervals along the slat at positions aligned with the ladder sets 20a-d. Lifting cords 24, fastened at one end to the foot rail 23 are threaded up through the apertures 22a of the slats 22, passing through holes (not visible in Figure 1) in the underside of the tubular body 18 into the interior of the tubular body 18, passing along the interior of the tubular body 18 and finally exiting the headrail assembly 12 via the side control assembly 14, where they dangle ready for use. When the lift cords 24 are pulled downwardly manually, they lift the foot rail 23 such that the slats 22 are drawn upwardly and overlaid in sequence permitting the blind assembly 10 to be raised. A lift cord control mechanism including a dog 25 that permits this and the reverse lowering operation to be carried out is described in more detail below.

The blind assembly 10 further comprises a wand 26, taking the form of a stiff member, which is connected to the side control assembly 14. The blind assembly 10 is constructed such that a push or pull motion applied by the user to the wand 26 causes a corresponding rotation of the tubular body 18 which through the ladder sets 20a-d imparts a rotary motion to the slats 22 causing them to tilt in unison. Figures 2(a-c) show the connection of a ladder set, using ladder set 20a as an example, to a representative section of the body portion 18b. The body portion 18b is a composite structure comprising a central strut 28 having a curved base 28a and a pair of walls 28b which upstand from the base 28a and extend at their distal ends inwardly and downwardly to form gripping portions 28c. The body portion 18b further comprises a pair of side wings 30 that affix to the walls 28b and a channel section 32 that affixes onto the walls 28b. The ladder set 20a is arranged to overlay the channel section 32 and the wings 30 and is clamped in fixed relation thereto by a cover 34. The outer surfaces of the base 28a, the wings 30 and the cover 34 together provide the tubular body 18 with a shape that is slat like providing not only an appearance that blends with the slats 22 but also enabling the body 18 itself to perform the role of a slat 22 in selectively blocking the passage of light. The body portion 18c has the same construction as the body portion 18b.

Referring to Figure 3, the side control assembly 14 comprises a support plate 36 by which the side control assembly 14 is attached to the fixed world via a mounting bracket 38. Referring to Figures 4 and 5, the support plate 36 carries a housing or casing 40 having a first fixed hollow shaft 41 projecting rightwards of the casing 40 and centred on an axis X-X serving as the axis of rotation of the body 18. The first hollow shaft 41 is rigidly coupled to the fixed world via the support plate 36 and the mounting bracket 38. The casing 40 has an elliptical cross-section that blends with the slat-shaped tubular body 18. The side control assembly 14 comprises a tilt control member 44 having a lever 46 which at one end thereof is provided with a connection bar 48 by which the wand 26 is attached to the tilt control member 44 and at the other end thereof is provided with a first gear wheel 50 that is externally toothed for only a fraction of its circumference. The first gear wheel 50 is mounted on the hollow shaft 41 for rotation about the axis X-X. The side control assembly 14 further comprises an internal shaft 49 fixed relative to the casing and defining an axis Y-Y that is parallel to the axis X-X. The side control assembly 14 further comprises a second gear wheel 52 mounted on the shaft for rotation about an axis Y-Y. The second gear wheel 52 is a one- piece member comprising a first second gear wheel portion 52a having external teeth at a first smaller radial distance from the axis Y-Y and a second second gear wheel portion 52b having external teeth at a second larger radial distance from the axis Y-Y. The teeth of the first second gear wheel portion 52a are meshed in operative engagement with those of the first gear wheel 50 of the tilt control member 44, whereby a unit rotation of the lever 46 gives rise to an amplified rotation of the second second gear wheel portion 52b resulting from the radial size differential of the first gear wheel 50 relative to the first second gear wheel portion 52a and the differential of the second second gear wheel portion 52b relative to a third gear wheel 60. The side control assembly 14 further comprises a wrapped spring assembly 54 comprising a wrapped spring 56 fitted in tight gripping relation to the hollow shaft 41 such that it is rotationally immobile with respect thereto and arranged such that the ends of the spring 56 are bent upwardly to form upstanding tangs 56a,b. The wrapped spring assembly 54 further comprises an actuator member 58 comprising the gear wheel 60 and a finger portion 62 projecting from the third gear wheel 60. The actuator member 58 is mounted on the hollow shaft 41 for rotation about the axis X-X and its teeth engage those of the second second gear wheel portion 52b. The finger portion 62 is arranged to project between the upstanding tangs 56a,b. The side control assembly 14 comprises a first body connector 64a. In Figure 4, the top portion of the first body

connector 64a has been omitted to make plainly visible the engagement of the tangs 56a, b and the finger portion 62. The complete first body connector 64a is visible in Figure 6(a). Referring to Figure 6(a), the body connector 64a comprises a circular, central through-hole 66 and recessed section 68 extending around a portion of the circumference of the through- hole 66 and bounded by side walls 68a,b. Referring back to Figures 4 and 5, the body connector 64a by means of the through-hole 66 is mounted for rotation on the hollow shaft 41 and the recessed section 68 receives the tangs 56a,b and the finger portion 62. The side control assembly 14 further comprises an indexing mechanism 81 comprising a clicking part 82 comprising a generally C-shaped spring element 82a having a cam 82b. The clicking part 82 is fixedly mounted to the shaft 49. The indexing mechanism 81 further comprises an indexing surface 83 forming part of the tilt control member 44 and presenting an arc of detents. The indexing mechanism 81 is arranged such that the cam 82b of the spring element 82a can engage successive detents on the indexing surface 83 as the tilt control member is rotated.

Under the driving action of the second second gear wheel portion 52b, the third gear wheel 60 may be driven in a clockwise or anti-clockwise direction. As an example, if it is assumed that the third gear wheel 60 is driven in a clockwise direction, the finger portion 62 is driven against the tang 56a. The driving force against the tang 56a acts against the resilience of the spring 56 causing it to slightly open and loosen its grip on the hollow shaft 41. The loosening of the spring's grip enables the whole spring to be forcibly rotated with respect to the hollow shaft 41. The rotation is somewhat reluctant as there is still abundant frictional engagement with the surface of the hollow shaft 41. As the whole spring 56 starts to rotate, the tang 56a comes into contact with the side wall 68a of the recessed section 68 hich causes the rotation of the body connector 64a. When the driving force applied to the third gear wheel 60 is

discontinued, the spring 56 relaxes back into tight engagement with the hollow shaft 41 locking it, and hence the body connector 64a, in a new relative orientation with the hollow shaft 41. Similarly, when the third gear wheel 60 is driven in an anticlockwise direction, the tang 56b acts against the other side wall 68b of the recessed section 68 and causes the rotation of the body connector 64a in the other direction. The body connector 64a has an external profile, including notably shoulder ribs 70, that is shaped to snugly engage as a male part within an end section of the strut 28 with the shoulder ribs 70 being retained by the gripping portions 28c. Through this engagement, when the body connector 64a is rotated in either direction as previously described, the whole body portion 18b rotates therewith.

The side control assembly 14 further comprises an axle 42 for transmitting torque from one side of the casing 40 to the other side of the casing 40. The axle 42 is positioned to rotate about the axis X-X; it passes through the through-hole 66 of the body connector 64a, through the hollow shaft 41 and the casing 40, and finally passing out through a second hollow shaft 74 which projects leftwards of the casing 40 as is best visible in Figure 3. A first clamping bush 72 secures the axle 42 in rotary unison with the first body connector 64a. A second body connector 64b, identical to the first body connector 64a, is mounted on the second hollow shaft 74 for rotation about the axis X-X. A second clamping bush 78 secures the second body connector 64b in rotary unison with the axle 42. Rotation axle brackets 80 are provided on the axle 42. Referring to Figure 3, the second body connector 64b, engages the strut of the body portion 18a in the same way that the first body connector 64a does the strut of the body portion 18b, whereby when the second body connector 64b is made to rotate as previously described the body portion 18a rotates in unison therewith.

Figures 7(a-b) show the intermediate _. support assembly 15 which provides support partway along the first blind assembly 10. The support assembly 15 comprises a support plate 96 by which the support assembly 15 is secured to the fixed world. The support plate 96 carries an arm 98 which carries a hollow tube 100. The tube 100 comprises hollow shafts 102, 104 that project in opposite directions from the arm 98 and are centred on the axis X-X. The shafts 102, 104 are rigidly coupled to the support plate 96. Third and fourth body connectors 64c, 64d, identical to the other body connectors, are mounted for rotation on the shafts 102, 104, respectively by clamping bushes 1 10, 1 12 respectively. The third and fourth body connectors 64c, 64d, engage with the body portions 18b, 18c respectively in the same way as the other body connectors engage with their respective body portions. A rotation bracket 1 14 mounted for rotation about the axis X-X is connected between the third and fourth body connectors 64c, 64d. In this way, as the body portion 18b is rotated as previously described, torque is transmitted through the rotation bracket 1 14 causing the other body connector 64d and, hence, the associated body portion 18c to rotate.

In the first blind assembly 10, the end support assembly 16 comprises the same structure as the intermediate support assembly 15. Referring to Figures 7(a-b), a fifth body connector 64e connects to the body portion 18c and a sixth body connector 64f connects to the body portion 18d.

It will be thus appreciated that by means of the above-described structure a rotary displacement of the first body connector 64a will result in a corresponding rotation of both the body portion 18b and the axle 42, and through the rotation of the axle 42 will also result in a corresponding rotation of the second body connector 64b and the body portion 18a.

Furthermore, the rotation of the body portion 18b by means of the intermediate support assembly 15 and the end support assembly 16 will cause corresponding rotations in the body portions 18c,d. In use, with the blind assembly 10 in the Figure 1 condition with the slats 22 at an approximately horizontal inclination, the slats 22 may be tilted anticlockwise to an almost vertical inclination by pushing upwardly on the wand 26. The upward movement of the wand 26 applies a torque to the first gear wheel 50 via the lever 46. A unit rotation of the first gear wheel 50 is amplified or stepped up into a proportional but greater rotation of the second gear wheel 52. The amplified rotation from the second gear wheel 52 then unlocks and drives the wrapped spring assembly 54 causing a corresponding amplified rotation in the first body connector 64, which, in turns, causes corresponding rotation of the whole body 18. The rotation of the first gear wheel 50 causes the rotation of the indexing surface 83 and thus the cam 82b to become positioned in successive detents of the indexing surface 83. The interaction of the indexing surface 83 with the cam 82b provides tactile feedback to the user. Additionally, this

interaction may also serve to hold the body 18 in a current rest position. In the illustrated embodiment, that role is subsidiary due to the locking action of the wrapped spring assembly 54. In other embodiments, the wrapped spring assembly 54 may be dispensed with and the interaction of the indexing surface 83 with the cam 82b may be arranged to be sufficient to hold the cam 82b in a single detent on the indexing surface 83 absent any user- applied forces to the tilt control member 44, whereby the indexing mechanism 81 may serve as the primary means by which the body 18 is held at the desired tilt angle. The use of the gear wheel 50 in converting a unit rotation of the lever 46 into greater rotation of the body 18 enables a tilt control member 44 having a connection point (connection bar 48, see Figure 4) that falls within the cross-sectional profile of the side control assembly 14 to be used without collision between the proximal end of the wand 26 and the slat- shaped body 18 or the top cross-beam of the window frame even when the slat-shaped body 18 and the slats 22 reach a light-minimising, almost vertical inclination.

In an alternative embodiment, the lever 46 may directly drive the wrapped spring assembly 54 without intermediate rotational amplification. In such a case, in order to guarantee that when the slat-shaped body 18 and the slats 22 reach light-minimising, almost vertical inclination no collision occurs between the proximal end of the wand 26 and the body 18 or the top cross-beam of the window frame, the connection point of the tilt control member 44 to the wand 26 should project outside the profile of the side control assembly 14 as illustrated in Figures 8(a-b).

An alternative embodiment is now described in which a detent

arrangement is provided between the hollow shaft 41 and body connector 64a in place of the wrapped spring assembly. This may be provided with or without the indexing arrangement described above. Furthermore, although illustrated with intermediate rotational amplification as described above, it could also be embodied with direct drive from the control member 44. Referring to Figure 9, it will be seen that this embodiment includes a support plate 36 and hollow shaft 41 equivalent to those described above. These components and those providing drive from the tilt control member 44 are equivalent to those described above and should be understood accordingly.

In the illustrated embodiment, the body connector 64a is integrally formed with an oval end plate 18e for one of the tubular bodies 18. This is an alternative and optional feature and, indeed, could be used with the other embodiments discussed here.

This embodiment makes use of a detent arrangement for releasably holding the body connector 64a, and hence its associated tubular bodies 18, at a predetermined relative rotational orientation relative to the shaft 41 and hence the support plate 36 and mounting bracket 38.

Although the detent arrangement could be provided in a number of different ways, for instance with one or more protrusions and recesses provided on opposing surfaces of the shaft 41 and body connector 64a, in the illustrated embodiment, the outer surface of the first shaft 41 includes an opening 41a at a predetermined rotational orientation. Although the opening 41a could take the form of an indent in the outer surface, in the illustrated embodiment, a recess is formed from a throughhole. It is sufficient for the opening 41a to be positioned axially along the shaft 41 so as to cooperate with the body connector 64a as required. However, in the illustrated embodiment, the opening 41a is formed as an axially extending slot. This may simplify production and also reduce the required tolerance for axially positioning the body connector 64a with respect to the shaft 41 and its assembly.

Figure 9 also illustrates a first clamping bush 72 which is provided for holding the body connector 64a axially on the shaft 41. As illustrated, the upper circumferential portion is chamfered, this chamfered shape being preferred according to space constraints not relevant to the present invention.

As illustrated in Figure 10, the body connector 64a has a generally circumferential inner surface which is configured to face the outer surface of the shaft 41. Two protrusions 164a and 164b face inwardly towards the outer surface of the first shaft 41. As will be explained in greater detail below, the two protrusions 164a, 164b enable the body connector to be releasably held in two respective orientations, both of which corresponding to closing of the associated slats. Of course, if it is desired only to hold the slats closed in one orientation, it will be sufficient to provide only one of the protrusions 164a and 164b. Similarly, embodiments would be possible with additional protrusions for releasably holding the body connector at intermediate angular positions.

In the illustrated embodiment, the two protrusions 164a and 164b are positioned at angles of approximately or substantially plus and minus 65° with respect to a central position - the Y-axis as illustrated. This results in releasably holding the body connector at plus or minus 65° for achieving maximum tilt angle of the slats. It will be appreciated that other angles could alternatively be chosen.

In the illustrated embodiment, the body connector 64a is driven by means of the finger 62 of the actuator member 58. However, whereas with the wrap spring embodiment, the finger 62 operates on tangs 56a and 56b of the spring 56, with this embodiment, it is possible for the finger portion 62 to act directly upon the body connector 64a. Indeed, other embodiments will be possible where the actuator member 58 and associated third gear wheel 60 are formed integrally with or attached to the body connector 64a. Similarly, for direct drive embodiments, it would be possible for the tilt control member 44 to be integral with or connected to the body connector 64a. In the illustrated embodiment, the recessed section 68 of the body connector 64a is shifted radially inward so as to be located at the same radius with respect to the X-X axis as the finger 62 of the actuator member 58. The recessed section 68 is further provided with a central slit 168 in which the finger 62 is received in the assembled condition.

The headrail assembly with mounting bracket 38 is illustrated in Figure 1 1 and its operation will be described with reference to Figures 12 A, 12B and 12C.

Figure 12A shows the side control assembly in a neutral position, in which the slats are open, ie extends substantially horizontally. To tilt the slats upward (left side as illustrated upward), to a closed condition, lever 46 of tilt control member 44 is tilted upward. This causes the finger 62 of the actuator member 58 to be rotated clockwise (in a manner similar to that described for the wrap spring embodiment). In other words, the finger 62 is rotated via the first gear wheel 50, which drives the second gear wheel 52, which in turn drives third gear wheel 60. As noted above, in an alternative embodiment, finger 62 could be integrally connected to the tilt control member 44.

Finger 62 extends in the central slit 168 of the recessed section 68 so that rotation of the finger 62 causes the first body connector 64a to rotate, thereby tilting the headrail and slats.

Once the finger 62 has been rotated by a predetermined angle (according to the position of protrusion or rib 164a), which as mentioned above is, in the illustrated embodiment, 65°, the left protrusion 164a will be located above the slot 41a in the shaft 41.

The protrusion 164a then engages with the slot 41a so as to releasably hold the body connector 64a with respect to the shaft 41. In this way, the slats are held in their tilted/ closed condition. Particularly where protrusions are provided in a resilient manner, it is possible for the opening in the shaft 41 to be provided at any angular orientation with the protrusions of the body connector positioned

appropriately. However, the illustrated embodiment, by positioning the slot 41a at the uppermost part of the shaft 41 can use gravity to releasably hold the body connector. In particular, as illustrated in Figure 12B, due to gravity acting on the headrail and the slats hanging therefrom, the body connector 64a moves downward such that the protrusion 164a enters the slot 41a and forms a mechanical lock, preventing the body connector 64a from counterclockwise rotation. Thus, once tilted to a closed position, the headrail and slats cannot be opened inadvertently, for example by the weight of the slats hanging therefrom.

It will be appreciated that, instead of rotating the lever 46 upward, it can be rotated downward (as illustrated) to tilt the slats to a closed position. In such a case, the right protrusion 164b (as illustrated) will be caught in the slot 41a when the lever 46 is rotated over about minus 65° according to the embodiment as described. This is illustrated in Figure 12C. Unlocking of the protrusion 164a and 164b is achieved by operating the lever 46 in the opposite direction. Thus, starting from the position of Figure 12B, the operating lever 46 is operated in a counterclockwise direction. This causes the finger 62 to rotate counterclockwise and exert a force on the body connector 64a that has an upward component and a sideward component (as illustrated in Figure 12B). The upward force component raises the body connector 604a and consequently lifts the protrusion 164a from the slot 41 A, thereby releasing the mechanical lock. Similarly, starting from the orientation of Figure 12C, to unlock the protrusion 164b, the lever 46 is rotated upward.

The illustrated embodiment includes an additional feature for providing secure engagement of the ribs 164a and 164b.

As illustrated particularly in Figure 10, the side walls 68a and 68b of the body connector 64a are provided with respective central cutaway portions 169a and 168b. The protrusions 164a and 164b are provided immediately adjacent/ above the respective cutaway portions 168a and 168b.

As illustrated in Figures 12B and 12C, at the time that the protrusions 164a and 164b respectively engage in the slot 41a, the cutaway portions 168a and 168b respectively allow the body connector 64a to move

downward slightly with the shaft 41 partly extending in the cutaway portions 168a and 168b respectively. Compared with the wrapped spring embodiment, this detent arrangement embodiment has the following advantages.

In the situation where the blind is closed such that the slats are

completely tilted upward or downward, the detent embodiment prevents the slats from being inadvertently tilted towards an open position.

Although the wrapped spring embodiment is highly advantageous, it is possible for the frictional force exerted by the spring to be not strong enough to resist movement of the slats to an open position. The detent arrangement has the advantage of allowing a lower operation force, because there is no need to overcome the frictional force exerted by the wrapped spring assembly 54. In this respect, it may be noted that when the slats are in an intermediate position (between their maximum upward tilted position and maximum downward tilted position), the slats are equally carried by both the front and back side of the ladder tapes. In this situation, the normal frictional forces suffice to hold the slats in position. No additional braking force is required. In a fully closed position, where the slats are tilted completely upward or downward, the side of the tape that has been lifted upward will carry most of the weight and will exert a reverse torque on the headrail. In this situation, an additional braking force is required. The wrapped spring embodiment provides the additional braking force at any orientation, whereas the detent embodiment provides the braking force at only the predetermined rotational orientations, for example the two opposite fully closed positions. Figures 13 to 16 illustrate the routing of the lifting cords 24 in the first blind assembly 10. Referring to Figure 13, the four lifting cords 24 enter the casing 40 of the side control assembly 14 through an opening 1 16 at the front side thereof. A lift cord control mechanism in the form of a conventional cord lock is located within the opening 1 16. The lift cord control mechanism comprises a dog 25 comprising a fixed upper jaw 25a and a lower moveable jaw 25b. The jaw 25b is mounted to pivot from the open position shown in Figure 13 to a closed position where it holds the lift cords 24 in engagement with the jaw 25a. The jaw 25b is biased to the closed position. The lift cords 24 pass vertically between the jaws 25a,25b of the dog 25 around a guide roll 1 18 which directs the lift cords 24 to travel in a generally horizontal direction along a passageway 120. The passageway 120 opens onto the first hollow shaft 41 and thus the lift cords 24 pass into the hollow shaft 41 and start their journey along the body 18. As shown in Figures 14 and 15, a first of the lifting cords 24 is routed through a hole 2 la in the underside of the body portion 18b and passes down through the slats 22 via apertures 22a where it is finally connected to the foot rail 23 (Figure 1). The other lift cords 24 continue along the inside of the body 18. Referring to Figure 16, a second of the lifting cords

24 is routed through a hole 21b in the underside of the body portion 18b and similarly passes down through the slats 22 where it finally connects to the foot rail 23. The two remaining lift cords 24 then pass through the tube 100 of the intermediate support assembly 15. One of the remaining lifting cords 24 is then routed through a hole 2 lc in the underside of the body portion 18c as is visible in Figure 16 and similarly passes down through the slats 22 where it finally connects to the foot rail 23. The other remaining lifting cord is similarly routed through a further hole in the body portion 18c. The further hole is not visible in the drawings.

In use, the biasing of the jaw 25b towards the jaw 25a results in the dog

25 locking the lifting cords 24 in a predetermined position. The strength of the locking grip between the jaws 25a,25b is sufficient to support the weight of all the slats 22 and the foot rail 23. If the user wishes to raise or lower the blind assembly 10, he displaces the lifting cords 24 laterally (i.e. towards or away from the user) in order to overcome the bias of the lower jaw 25b, separate the jaws 25a,25b and thereby unlock the dog 25. Once this is achieved, the lifting cords 24 may then be pulled downwardly in order to raise the blind assembly 10 or allowed, under the weight of the slats 22 and the foot rail 23, to be drawn upwardly in order to lower the blind assembly 10, while maintaining the above-mentioned lateral displacement of the lifting cords 24. Once the desired position of the blind assembly 10 is achieved, the lateral displacement of the lifting cords 24 is discontinued and the dog 25 resumes its closed position thereby locking the blind assembly 10 in the desired position. It will be appreciated that the above-described routing of the lifting cords 24 isolates the lifting cords 24 from the inner workings of the side control assembly 14 and is also not affected by the orientation of the body 18.

A second Venetian blind assembly 10 is shown in Figure 17. The second blind assembly is identical to the first blind assembly except insofar as is shown in drawings or as specifically stated below. In the second blind assembly 10, the side control assembly 14 is located at the very end of the body 18. As a result, the second blind assembly 10 does not include the axle 42 or related components for transmitting torque from one side of the casing 40 to the other. In addition, the end support assembly 16 rather than being constructed like the intermediate support assembly 15 is rather more based on the construction of the side control assembly 14. The end support assembly 16 comprises a support plate 36 by which the support assembly 16 is secured to the fixed world. The support plate 36 carries a housing or casing 40 having a fixed hollow shaft 84 projecting leftwards of the casing 40 and centred on the axis X-X. The fixed hollow shaft 84 is rigidly coupled to the support plate 36. A closing member 88 closes off an opening in the casing 40 that corresponds to the opening 1 16 in the side control assembly 14. The fifth body connector 64e is mounted for rotation on the fixed shaft 84 about the axis X-X via a filling bush 86 and a clamping bush 92. The fifth body connector 64e engages with the end of the body portion 18c in the same way as the body connectors 64a, 64b engage with their respective body portions. The user adjusts the tilting of the slats and raises and lowers the blind assembly exactly as per the first blind assembly 10. In addition, the routing of the lift cords 24 is the same as the first blind assembly as illustrated in Figure 19.

It will be appreciated that, in other embodiments, the side control assembly 14 may be positioned to the left-hand side of the blind assembly 10 and the support assembly 16 may be positioned to the right-hand side of the blind assembly 10. Furthermore, shorter blind assemblies may not require an intermediate support assembly 15.

List of parts

Venetian blind assembly 10

Headrail assembly 12

Side control assembly 14

Intermediate support assembly 15

End support assembly 16

Tubular body 18

First tubular body portion 18a

Second tubular body portion 18b

Third tubular body portion 18c

Fourth tubular body portion 18d

Oval end plate 18e

Ladder sets 20a-d

Holes 21a, 21b, 21c

Slats 22

Apertures 22a

Foot rail 23

Lifting cords 24

Dog 25

Upper jaw 25a

Moveable jaw 25b Strut 28

Base 28a

Walls 28b

Gripping portions 28c

Side wings 30

Channel section 32

Cover 34

Support plate 36

Mounting bracket 38

Housing or Casing 40

First hollow shaft 41

Slot 41a

Axle 42

Tilt control member 44

Lever 46

Connection bar 48

Shaft 49

First gear wheel 50

Second gear wheel 52

Second Gear wheel portions 52a,b

Wrapped spring assembly 54

Spring 56

Tangs 56a,b

Actuator member 58

Third gear wheel 60

Finger portion 62

First body connector 64a

Second body connector 64b

Third body connector 64c

Fourth body connector 64d

Fifth body connector 64e

Sixth body connector 64f

Through-hole 66

Recessed section 68 Side walls 68a,b

Shoulder ribs 70

First clamping bush 72

Second hollow shaft 74

Second clamping bush 78

Rotation axle brackets 80

Indexing mechanism 81

Clicking part 82

Spring element 82a

Cam 82b

Indexing surface 83

Fixed shaft 84

Filling bush 86

Closing member 88

Clamping bush 92

Support assembly 94

Support plate 96

Arm 98

Tube 100

Shafts 102, 104

Clamping bushes 1 10, 1 12

Rotation bracket 114

Opening 1 16

Guide roll 1 18

Passageway 120

Protrusions 164a, 164b

Central slit 168

Cutaway portions 168a, 168b

Claims

1. A headrail assembly for a blind assembly, comprising:

a tubular body from which the slats of the blind assembly are to be suspended; and

a control assembly comprising an attachment part by which the tubular body is to be attached to the fixed world, a housing that is fixed relative to the attachment part, a tilt control mechanism, associated with the housing, comprising a tilt control member via which a user- applied torque is transmitted to the tilt control mechanism and a body connector coupled between the tilt control mechanism and the tubular body, and a lift cord control mechanism, associated with the housing, comprising lift cords;

wherein the lift cords are routed so as to pass from the lift cord control mechanism, through the housing and into the tubular body via a hollow fixed shaft, forming part of the housing, about which the body connector and the tubular body are arranged to rotate in unison when the body connector is subjected to torque transmitted from the tilt control member.

2. A headrail assembly as in claim 1 , wherein the tubular body is generally slat shaped.

3. A headrail assembly for a blind assembly, comprising:

- a tubular body from which the slats of the blind assembly are to be suspended; and

a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a housing having a first shaft that is fixed relative to the attachment part, a tilt control mechanism, associated with the housing, and comprising a tilt

control member by which the tilt control mechanisim is controlled, and a body connector coupled between the tilt control mechanism and the tubular body; wherein the tilt control mechanism comprises a rotation

amplification device coupled between the tilt control member and the body connector that is constructed to translate a unit rotation of the tilt control member into a larger corresponding rotation of the body connector.

4. A headrail assembly as in claim 3, further comprising a wrapped spring assembly coupled to the tilt control member and operable to allow the rotation of the tubular body when the tilt control member is rotated and to hold the tubular body rotationally immobile when the tilt control member is at rest.

5. A head rail assembly for a blind assembly, comprising:

a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a first shaft that is fixed relative to the attachment part, a body connector rotatably mounted on the first shaft and for connection to a tubular body, from which slats of the blind assembly are to be suspended, arranged to rotate in unison with the body connector, a tilt control member coupled to the body connector for transmitting a user-applied torque to the body connector; and

6. A headrail assembly as in claim 5 wherein the at least one predetermined relative rotational orientation includes two opposite orientations, each for positioning the body for closing the slats.

7. A head rail assembly as in claim 5 or 6 wherein

the first shaft includes a circumferential outer surface and a recess in the outer surface at a predetermined rotational orientation; and the body connector includes at least one protrusion facing the outer surface of the first shaft and configured to engage with the recess so as to releasably hold the first shaft and the body connector at a respective at least one predetermined relative rotational orientation.

8. A head rail assembly as in claim 7 wherein the recess is

positioned relative to the attachment part such that, when the attachment part is attached to the fixed world, the recess faces upwardly from the first shaft.

9. A head rail assembly as in claim 7 or 8 wherein the body connector includes two said protrusions facing the outer surface of the first shaft and spaced at different angular orientations.

10. A head rail assembly as in claims 5, 6, 7, 8 or 9 further

comprising a rotation amplification device coupled between the tilt control member and the body connector that is constructed to translate a unit rotation of the tilt control member into a larger corresponding rotation of the body connector.

1 1. A headrail assembly as in any of claims 1 to 10, further comprising an indexing mechanism that provides tactile feedback to the user during operation of the tilt control mechanism.

12. A headrail assembly as in claim 11 , wherein the indexing mechanism is constructed to hold the tubular body in a rest position.

13. A headrail assembly as in any of claims 1 to 12, wherein the tubular body is generally slat shaped.

14. A headrail assembly for a blind assembly, comprising

a control assembly comprising an attachment part by which the headrail assembly is to be attached to the fixed world, a housing having a first shaft that is fixed relative to the attachment part, a wrapped spring assembly mounted to the first shaft, a tilt control member coupled to the wrapped spring assembly for transmitting a user-applied torque to the wrapped spring assembly; and a tubular body, from which slats of the blind assembly are to be suspended, arranged to rotate in unison with the wrapped spring

assembly;

wherein the control assembly is constructed such that, responsive to a user-applied torque from the tilt control member, the wrapped spring assembly is released from a gripping condition in which it and the tubular body are held rotationally immobile with respect to the fixed shaft to a rotating condition in which it and the tubular body rotate in unison with respect to the fixed shaft.

15. A headrail assembly as in claim 14, constructed such that when the user-applied torque ceases the wrapped spring assembly returns to the gripping condition in which it is rotationally immobile.

16. A headrail assembly as in claim 14 or 15, wherein the tilt control member comprises a lever mounted for rotation about the first shaft, and the control assembly comprises a control wand connected to an end of the lever remote from the first shaft by which the user applies

said torque to the wrapped spring assembly.

17. A headrail assembly as in any of claims 14 to 16, wherein the tilt control member comprises a gear wheel portion mounted for rotation about the first shaft and the wrapped spring assembly comprises a spring wrapped around the first shaft and an actuator member having a gear wheel portion and a finger portion for interacting with the spring.

18. A headrail assembly as in claim 17, wherein the control

assembly comprises an intermediate gear assembly operatively connected between the gear wheel portion of the tilt control member and the gear wheel portion of the actuator member and constructed to translate a unit rotation of the gear wheel portion of the tilt control member into a larger corresponding rotation of the gear wheel portion of the actuating member.

19. A headrail assembly as in any of claims 16 to 18, wherein the tubular body is slat shaped and the connection point between the control wand and the lever sits within a cross- sectional profile of the tubular body, and wherein, in use, the control wand is able to drive the tilting of the tubular body into a light-minimising, near vertical inclination without collision with the tubular body or the fixed world.

20. A headrail assembly for a blind assembly, comprising:

a tubular body, comprising a first body portion and a second body portion, from which the slats of the blind assembly are to be suspended;

a support assembly comprising an attachment part for attaching the headrail assembly to the fixed world, a hollow tube fixedly coupled to the attachment part, first and second body connectors mounted for rotation about first and second ends of the hollow tube respectively and coupled to the first and second body portions respectively to rotate in unison therewith, and a bracket, coupling the first and second body connectors, for transmitting torque from one of said body connectors to the other of said body connectors; and

a control assembly comprising a lift cord control mechanism via which lifts cords are routed into the tubular body;

wherein a said lift cord is routed from one of said body portions to the other of said body portions through the hollow tube.

21. A blind assembly comprising a headrail assembly as in any preceding claim and further comprising a plurality of slats suspended from the headrail assembly, and a plurality of ladder sets connected to the body and the slats such that rotation of the body causes a corresponding tilting motion in the slats.

22. A head rail assembly as in any of claims 1 to 21, wherein the control assembly is a side control assembly on only one side of the tubular body.