GB2322153A - Headrail and two-piece carrier assembly for vertical slat blinds - Google Patents

Abstract

A headrail and carrier assembly for the suspension of vertical slat blinds comprises a number of carriers 1 which are arranged to slide in a headrail 3. The carriers each include a spacer component 21 and a carrier body 22. The spacer components 21 are moulded onto a pair of spacer cords 25 and 26, which extend along opposite sides of the headrail, to determine the maximum spacing between the carriers. The draw cords (not shown) lie freely within the recesses formed by protrusions 28 and 29. The cords and components 21 are contained within a plastic extruded sub-compartment 9 within the headrail which is partially defined by inwardly-extending flanges 16 and 17 separated by a gap 18. The components 21 are engaged with the carrier bodies 22 through the gap with a rotatable connection 30, 35. The flanges 16 and 17 prevent the spacer cords interfering with the operation of the tilt bar 2 and bevel gear assembly (fig. 2 not shown) used to rotate the slats axially.

Description

VERTICAL SLAT BLINDS TECHNICAL FIELD OF THE INVENTION This invention relates to vertical slat blinds.

BACKGROUND A typical form of vertical slat blind is disclosed in GB 1 286 195. Such blinds generally include a series of slats suspended from respective carriers (commonly known as trucks) which are mounted to slide along a headrail which is typically of invertedchannel section. The slats are arranged to pivot about vertical axes by means of a tilt rod which passes through all the carriers and is coupled to each slat via a pair of gears and a slipping clutch incorporated within the carrier. The maximum spacing between the carriers is generally determined by metal or plastics spacer strips. Such a strip is fixed to each carrier, passing through the adjacent carrier such that the adjacent carriers can move together but are unable to move more than a certain distance apart.

In GB 1 578 959 a slotted belt is used to rotate the slats, the same best being used to move the slats along the head rail. The belt engages one side of a toothed wheel which is coupled to each slat via a slipping clutch. The maximum spacing between the carriers which incorporate the toothed wheels is determined by a string of beads which is pressed into a recess formed in a plastics clip which, in turn, is snap-engaged with the carrier.

In another known form of vertical slat blind a pair of cords are attached directly to the slats on opposite sides of their pivot axes so that the slats can be rotated by moving the cords in opposite directions. (See GB 188 641 for example.) The cords also determine the spacing between the slats. In GB 2 122 675 A two sections of a cord on opposite sides of the pivot axes are arranged to rotate the slats by frictionally engaging the underside of discs connected with the slats. In this case the maximum spacing between the slats is determined by a separate beaded cord or by respective spacer strips associated with each slat.

The present invention seeks to provide a new and inventive form of vertical blind.

SUMMARY OF THE INVENTION The present invention proposes a vertical slat blind of the kind in which the slats are pivotally suspended from respective carriers which are arranged to slide in a head rail of inverted channel section, in which a pair of spacer cords extend within the head rail along opposite sides thereof, and said carriers each include a spacer component which is moulded onto both of said cords to determine the maximum spacing between the carriers, and the spacer cords and components are contained within a longitudinallyextending sub compartment within the headrail which is partially defined by opposed inwardlyextending walls which are separated by a gap.

Such means of spacing the carriers allows the manufacturing cost to be reduced and makes the head rail easy to assemble. In particular, the ease of assembly enables the head rail to be easily cut to length by the user.

The sub-compartment containing the spacer cords is preferably located within an upper region of the headrail.

Each carrier preferably comprises a carrier body from which the respective slat is suspended. Each carrier body is preferably separable from its associated spacer component. The spacer components and the carrier bodies are preferably mutually engaged through the said gap. Preferably the spacer components and carrier bodies are mutually engaged with a rotatable connection.

The subcompartment is preferably formed by an inner extrusion of inverted channel section. The head rail may be extruded of metal, but the inner extrusion is preferably formed of plastics. With this form of construction the outer head rail can still be used on its own with conventional carriers but the inner part can be added for use in the present invention.

The head rail preferably contains a draw cord for moving the carriers along the rail. In order to permit easy assembly and allow removal of trucks when cutting the rail to length the draw cord is preferably inserted into guide openings in the spacer components. The guide openings preferably have open mouths through which the draw cord is inserted, thus avoiding having to thread the trucks onto the cord.

The carrier bodies preferably each comprise a moulded plastics housing. The cost of the trucks may be further reduced if the housing is moulded in two cooperating parts which are connected by an integral hinge.

BRIEF DESCRIPTION OF THE DRAWINGS The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: Figure 1 is a transverse section through a head rail assembly of a vertical slat blind in accordance with the invention, and Figure 2 is an exploded perspective view of the carrier assembly shown in Fig. 1.

DETAILED DESCRIPTION OF THE DRAWINGS Referring to Fig. 1, the headrail assembly is incorporated in a vertical slat blind in which the slats (not shown) are pivotally suspended from respective carriers 1 which are mounted to slide along a tilt rod 2 in a head rail 3. The ends of the head rail are normally closed by end caps (not shown).

The head rail 3 is of a conventional form, being extruded from aluminium.

The rail is of inverted channel section, with the open bottom of the section having narrow inturned flanges 4 and 5. The top of the rail is provided with opposed side recesses 6 and 7 which may be used in securing the headrail.

A plastics extrusion 8 is secured within the top portion of the head rail to divide the interior of the rail into upper and lower sub-compartments 9 and 10 respectively. The extrusion 8 is also of inverted channel section with opposed shoulders 11 and 12 to accommodate the recesses 6 and 7. The top wall 13 of the extrusion has a pair of spaced internal guide walls 14 and 15 whilst the bottom of the extrusion has a pair of opposed inturned flanges 16 and 17 which are separated by a slot-shaped gap 18. The flanges 16 and 17 further have small upstanding lips 19 and 20.

The extrusion 8 may be adhesively bonded into the outer rail 3, held by friction, or secured in any other suitable manner. An advantage of this form of construction is that the rail 3 can still be used with conventional carriers without the extrusion 8. It will be appreciated that the rail 3 could be formed of plastics if desired, and similarly, the inner extrusion 8 could be formed of metal. If the option of using the outer rail with conventional carriers is not required the rail 3 and extrusion 8 could be formed as a single extrusion of suitable section, with transverse internal flanges 16 and 1 7.

Referring also to Fig. 2, the carriers 1 comprise a head component 21 and a carrier body 22. The head component 21 is generally in the form of a solid rectangular plate 23. The lower face of the component is securely moulded onto a pair of flexible spacer cords 25 and 26 which run substantially parallel within the extrusion 8 on opposite sides of the carrier. A series of such components 21 are moulded onto the cords at regular spaced intervals, so that the cords determine the maximum spacing between the carriers. The components 21 can be moulded onto the cord in a continuous length, from which the desired number of head components are removed and threaded into the end of the extrusion 8.

The upper surface of the component 21 is provided with a pair of opposed guides 28 and 29 for a draw cord (not shown) which travels along the extrusion 8. The guides have open mouths which retain the cord but which allow the cord to be pressed into the guides without having to thread the carriers onto the cord. The cord is secured to the end carrier 21 (e.g. by means of a self-tapping screw) so that the carriers can be moved along the head rail by means of the draw cord, but the cord is free to slide in the guides 28, 29 of the remaining carriers.

When the carriers are moved to one end of the rail 3 the spacer cords 25, 26 bunch up within the extrusion 8 at the sides of the carrier 21, but since the cords are retained within the upper compartment 9 they are prevented from interfering with movement of the carrier bodies 22, and there is no risk of them hanging down through the bottom of the headrail.

The underside of the head component 21 has a short depending circular spigot 30 (Fig. 1) which is positioned centrally in the slot 18.

Referring to Fig. 2, the carrier body 22 comprises a housing 32 which is conveniently moulded in two similar mating halves, only one of which is shown in the drawings. The two halves may be secured together by welding and/or retaining formations, but they are preferably joined by an integral hinge. The top of the housing 32 is provided with a cylindrical socket 35 which receives the spigot 30 such that the carrier body 22 is constrained to move along the rail 1 with the carrier 21. The housing 32 contains and rotatably guides a first gear member 33 having a central opening 34 which is shaped for driving engagement with splines formed on the tilt rod 4, which is rotatably mounted in the end caps of the head rail. The carrier is however free to slide along the tilt rod, assisted by opposed wheels 36 and 37 which run on the flanges 4 and 5, being mounted on stub shafts 38 and 39 formed on the housing 32.

During assembly, the rotatable connection formed by the spigot 30 and socket 35 allows the carrier body 22 to be engaged with the carrier 21 through the bottom of the head rail and rotated through 90" prior to insertion of the tilt rod. The wheels 36 and 37 and the sides of the housing 32 form an overcentre action with the head rail as the body 22 is rotated, so that the carrier body is retained within the head rail before the tilt rod is inserted. Such an arrangement allows for easy replacement of the carrier body if required without having to dis-assemble the entire head rail. It is only necessary to remove an end cap and the tilt rod.

The gear 33 has a ribbed or toothed bevel formation 40 which driveably engages a complementary bevel 41 formed on a second gear 42. The gear 42 is mounted to rotate about a vertical axis within a cylindrical collar 43 formed on the bottom of the housing 32 and positioned to project through the bottom of the head rail 3. The second gear 42 has a cylindrical housing portion 44 which receives a hook-like hanger 45 from which a slat is suspended in use. The gear 42 engages the hanger 45 via a suitable slipping clutch arrangement (not shown) which may be of known form. The action of the clutch is such that when the gears 33 and 42 are rotated by the tilt rod 4 the slat rotates with the gear 42, but when the slat reaches its limit of rotation the clutch slips so that the tilt rod can continue to be rotated without rotation of the slat.

The described arrangement allows the manufacturing costs to be substantially reduced whilst at the same time making the head rail very easy to assemble and reliable in operation. Such ease of assembly also allows the head rail to be easily cut to length and reassembled by the user. When the required length of the assembly has been measured and the number of carriers to be removed has been determined, one of the end caps is removed and the tilt rod 4 is withdrawn. The carriers to be removed are pulled from the open end of the head rail and the spacer cords 25, 26 are cut to separate the unwanted carriers. The draw cord is simply pulled out of the openings 28, 29 and the separated carriers are discarded. The head rail is then cut to length, the tilt rod re-inserted, and the end cap replaced.

Although the above example described the common form of vertical slat blind in which a tilt rod is used to rotate the slats it will be appreciated that the slats could also be rotated by a tilt cord for example, which runs along the lower compartment 10 as in GB 2 122 675 A for example.

Whilst the above description lays emphasis on those areas which, in combination, are believed to be new, protection is claimed for any inventive combination of the features disclosed herein.

Claims (15)

1. A vertical slat blind of the kind in which the slats are pivotally suspended from respective carriers which are arranged to slide in a head rail of inverted channel section, in which a pair of spacer cords extend within the head rail along opposite sides thereof, and said carriers each include a spacer component which is moulded onto both of said cords to determine the maximum spacing between the carriers, and the spacer cords and components are contained within a longitudinally-extending subcompartment within the headrail which is partially defined by opposed inwardly-extending walls which are separated by a gap.

2. A vertical slat blind according to Claim 1, in which the subcompartment containing the spacer cords is located within an upper region of the head rail.

3. A vertical slat blind according to Claim 1 or 2, in which each carrier comprises a carrier body from which the respective slat is suspended.

4. A vertical slat blind according to Claim 3, in which each carrier body is separable from its associated component.

5. A vertical slat blind according to Claim 4, in which the spacer components and the carrier bodies are mutually engaged through the said gap.

6. A vertical slat blind according to Claim 5, in which the spacer components and carrier bodies are mutually engaged with a rotatable connection.

7. A vertical slat blind according to any preceding claim, in which the sub-compartment is formed by an inner extrusion of inverted channel section.

8. A vertical slat blind according to Claim 7, in which the headrail is extruded of metal.

9. A vertical slat blind according to Claim 7 or 8, in which the inner extrusion is formed of plastics.

10. A vertical slat blind according to any preceding claim, in which the head rail contains a draw cord for moving the carriers along the rail.

11. A vertical slat blind according to Claim 10, in which the draw cord is inserted into guide openings in the spacer components.

12. A vertical slat blind according to Claim 11, in which the guide openings have open mouths through which the draw cord is inserted.

1 3. A vertical slat blind according to any preceding claim, in which the carrier bodies each comprise a moulded plastics housing.

14. A vertical slat blind according to Claim 13, in which the housing is moulded in two co-operating parts which are connected by an integral hinge.

15. A vertical slat blind substantially as described with reference to the drawings.