WO2018195580A1

WO2018195580A1 - Motor for a spring assisted roller blind

Info

Publication number: WO2018195580A1
Application number: PCT/AU2018/000057
Authority: WO
Inventors: Grant Norton
Original assignee: Blindware Pty Ltd
Priority date: 2017-04-24
Filing date: 2018-04-23
Publication date: 2018-11-01

Abstract

A motorised system for a spring assisted roller blind, the system comprising: a motor having a tubular motor body and a drive spindle; a bi-directional spring clutch operative to engage the tubular motor in one of two modes, the first mode being to frictionally engage the motor body in a first direction of movement, and a second mode being to disengage the motor body, and a rotatable cylinder for winding a sheet of blind fabric.

Description

MOTOR FOR A SPRING ASSISTED ROLLER BLIND

FIELD OF INVENTION

[0001] The present invention relates to the field of motors for spring assisted roller blinds.

[0002] In one form, the invention relates to a motor according to the present invention in combination with an adjustable spring.

BACKGROUND ART

[0003] It is to be appreciated that any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the present invention. Further, the discussion throughout this specification comes about due to the realisation of the inventor and/or the identification of certain related art problems by the inventor. Moreover, any discussion of material such as documents, devices, acts or knowledge in this specification is included to explain the context of the invention in terms of the inventor's knowledge and experience and, accordingly, any such discussion should not be taken as an admission that any of the material forms part of the prior art base or the common general knowledge in the relevant art in Australia, or elsewhere, on or before the priority date of the disclosure and claims herein.

[0004] A standard clutch operated roller blind system of the prior art typically includes a rectangular sheet of flexible fabric having one end secured to a rotatable cylinder, and the opposite, free end secured to a weight bar. The fabric is typically referred to as a blind, awning or shade which is extended over an area or an opening in a wall. The ends of the cylinder are supported by brackets mounted on a structure such as a wall or window frame.

[0005] A winder comprising a clutch and a manual or automatic winding mechanism is located at a first end of the cylinder and can be used to extend or retract the fabric. Typically, a user controls the rotation of the winder and cylinder by a cord or chain, or alternatively the user controls a small motor that rotates the cylinder. An idler at the other one end of the cylinder rotates relative to the supporting bracket. The clutch prevents the fabric from unrolling from the cylinder under the fabric's own weight.

[0006] If the fabric is particularly heavy, such as when the area to be covered by the blind is very large, the cylinder may be spring assisted. The spring winds and tightens when the blind is lowered by an operator so that upon lifting the blind, the spring can release stored energy and assist the operator to roll the fabric back onto the cylinder with concomitant retraction and raising of the blind. The length of the spring determines the maximum number of rotations the cylinder will be able to make, which in turn dictates the maximum height of the blind for a given cylinder diameter.

[0007] Optimally, the operating force required to be exerted by the user is constant during operation and the torque exerted on the cylinder by the fabric and weight bar during retraction and extension of the fabric is perfectly counterbalanced by the spring unit. If the torques created by the fabric and weight bar less the counterbalance torque created by the spring are not constant, the effort required to pull the cord or chain to lift and lower the roller blind is uneven and varies as the blind fabric travels between the fully retracted and fully extended positions.

[0008] Thus, for perfectly balanced, smooth operation of the roller blind, the spring torque (determined by characteristics such as wire diameter, spring diameter and length) must match the characteristics of the blind. Accordingly, the spring may be specifically selected to match the intended application. Alternatively, the spring may be adjustable, such as the adjustable spring described in provisional Australian patent application AU- 2016 903675 which can be altered to match the size and weight of the blind and near perfectly offset to torque of the extending or retracting blind.

[0009] As mentioned above, a user may control the rotation of the winder and cylinder by pulling on a cord or chain, or alternatively the user may control a small motor that fits inside the cylinder and causes the cylinder to rotate. The motor is typically a DC motor and can be battery operated or powered from a solar panel or power transformer. Typically, the motors can vary from 6V to 24V AC or DC but because their torque is very low (limited to about 1 Nm) the motors of the prior art have only been suitable for small blinds. [0010] Although DC motors of 3 to 6 Nm maximum torque have been used to operate larger blinds, they are generally too large to fit inside the smaller cylinder diameters in common use for smaller blinds.

[001 1] Accordingly, there is an ongoing need for improved operation of DC powered motorised blinds used with spring assists.

SUMMARY OF INVENTION

[0012] An object of the present invention is to alleviate at least one disadvantage associated with the related art.

[0013] It is an object of the embodiments described herein to overcome or alleviate at least one of the above noted drawbacks of related art systems or to at least provide a useful alternative to related art systems.

[0014] In a first aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

(ii) a bi-directional spring clutch operative to engage the tubular motor in one of two modes, the first mode being to frictionally engage the motor body in a first direction of movement, and a second mode being to disengage the motor body,

(iii) a rotatable cylinder for winding a sheet of blind fabric.

[0015] In another embodiment of the present invention the tubular motor body includes an end housing. Thus in a second aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising;

(i) a motor having a tubular motor body, an end housing and a drive spindle, (ii) a bi-directional spring clutch operative to engage the tubular motor in one of two modes, the first mode being to frictionally engage the motor end housing in a first direction of movement, and a second mode being to disengage the motor end housing,

(iii) a rotatable cylinder for winding a sheet of blind fabric.

[0016] In a third aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

(ii) a bi-directional spring clutch at least partly encircling the tubular motor,

(iii) a rotatable cylinder for winding a sheet of blind fabric, wherein the drive spindle causes the rotatable cylinder to rotate while the tubular motor body remains stationary.

[0017] In a further embodiment of the present invention, when the tubular motor body includes an end housing, the spring of the bi-directional spring clutch is associated with the end housing. Thus, in a fourth aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body, an end housing and a drive spindle,

(ii) a bi-directional spring clutch,

(iii) a rotatable cylinder for winding a sheet of blind fabric, wherein the drive spindle causes the rotatable cylinder to rotate while the tubular motor body remains stationary. [0018] In a fifth aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

(ii) a bi-directional spring clutch having, one or more springs encircling the tubular motor body, the springs including tangs, a control cover including at least two control sectors for interaction with the tangs, a clutch housing enclosing the one or more springs and the control cover,

(iii) a rotatable cylinder for winding a sheet of blind fabric, wherein the drive spindle is coupled to the clutch housing and the rotatable cylinder and causes the rotatable cylinder to rotate while the tubular motor body remains stationary.

[0019] In a further embodiment of the present invention, when the tubular motor body includes an end housing, the spring of the bi-directional spring clutch at least partly resides within the end housing and the spring tangs interact with control sectors of the end housing. Thus, in a sixth aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind, the system comprising

(i) a motor having a tubular motor body, an end housing and a drive spindle,

(ii) a bi-directional spring clutch having, one or more springs associated with the end housing the tubular motor body, the springs including tangs, the end housing including at least two control sectors for interaction with the tangs. a clutch housing enclosing the motor, (iii) a rotatable cylinder for winding a sheet of blind fabric, wherein the drive spindle is coupled to the clutch housing and the rotatable cylinder and causes the rotatable cylinder to rotate while the tubular motor body remains stationary.

[0020] During operation, the motor remains stationary while the rotation of the spindle drives the clutch housing and the rotatable cylinder. In this manner the fabric is rolled off or on the cylinder, extending or retracting the fabric over an area or opening.

[0021] The clutch prevents the fabric from unrolling from the cylinder under the fabric's own weight. Specifically, the tangs on each spring key into the control cover and cause the cylinder to rotate. The clutch springs thus operate as the brake against the weight of the blind fabric as it rolls off the cylinder. This is in contrast to systems of the prior art which typically include an electromagnetic disc brake and do not include a clutch function.

[0022] In a further aspect of embodiments described herein there is provided a motorised system for a spring assisted roller blind according to the present invention which further comprises an adjustable spring assist.

[0023] In a particularly preferred embodiment of the present invention, the adjustable spring is at a first, idler end of the cylinder and the motor is at a second, motor driven end.

[0024] The adjustable spring can hold tension (as it is pre-tensioned) to equalise loads applied by the weight of the blind fabric. A particularly preferred adjustable spring is described in Australian provisional patent application AU-2016903675. The adjustable spring is a torsion spring comprising coils of constant or variable diameter, having a longitudinal axis, a first spring end and a second spring end and a dampener that can be located at a predetermined length along a longitudinal axis of the torsion spring. Tightening a first spring end of the helical spring against the dampener increases the spring constant by reducing the number of active coils. [0025] Typically the motor used in the system of the present invention has very low torque, that is, less than about 0.5 Nm. If the motor is used in conjunction with an adjustable spring, the required torque needed to operate the blind may be less than about 0.3 Nm, perhaps between about 0.1 and 0.2 Nm. This is significantly less than the torque required by motors for systems of the prior art.

[0026] Preferably the motor of the present invention is attached to a battery pack abutting the motor, or a rechargeable battery that is located within the motor. The battery pack may be located within the cylinder on which the blind fabric is wound. The battery may be rechargeable using a solar cell or power transformer. Alternatively, the motor can be powered directly from a power transformer that is connected to the motor and produces the matching voltage needed by the motor. In this second case, batteries are not required.

Control of Operation

[0027] In a preferred embodiment, operation of the system of the present invention can be controlled using a wand that can be removably attached adjacent an end of the motor. A wand is particularly preferred in view of the fact that blind control chains and cords of the prior art pose a significant risk to children.

[0028] In a preferred embodiment the wand includes a manual slide for controlling operation of the motor. Typically, the slide can be moved manually in a longitudinal direction along part of the wand to actuate the tubular motor and control the position of the blind. Moving the slide in a first direction causes extension of the fabric, while moving the slide in a second, opposite direction causes retraction of the fabric.

[0029] Circuitry is provided to facilitate communication between the slide and the motor of the present invention. Once the circuitry is programmed with the maximum and minimum distance of fabric travel, the blind can be made to stop at any position corresponding to the slide position. The circuitry may include a circuit card to enable user control via any convenient communication protocol such as Zigbee, WiFi, Infrared data Association (IrDA), Bluetooth, ultra-wideband (UWA) and Z-wave. [0030] In another aspect of embodiments described herein there is provided a method of operating the spring assisted roller blind of the present invention comprising the step of: using a controller to activate the motor such that the drive spindle causes the cylinder to rotate while the tubular motor body remains stationary, and using the controller to deactivate motor to slow or cease rotation of the cylinder.

[0031] Preferably the controller is a wand comprising a slide actuator to activate and deactivate the motor. In another preferred embodiment the controller is a wireless transmitter which communicates instructions for activation and deactivation to circuitry in the motor system.

[0032] Preferably the controller of the spring assisted blind comprises a wand with a manual slider, wherein the distance of linear movement of the manual slider is related, preferably proportional, to the linear distance of movement of the blind.

[0033] In a particularly preferred embodiment of the motorised system of the present invention, a variable resistor operates in response to the slider, the variable resistor having an output voltage proportional to movement of the slider between a first slider limiting position and a second slider limiting position, and wherein, in response to the output voltage, a drive signal from a slide controller causes the motor to turn the rotatable cylinder and move the sheet of blind fabric correspondingly between a first blind fabric limiting position and a second limiting position.

[0034] Other aspects and preferred forms are disclosed in the specification and/or defined in the appended claims, forming a part of the description of the invention.

[0035] In essence, embodiments of the present invention stem from the realization of that transferring motive power directly to the cylinder on which the fabric of a spring roller blind is wound can be achieved at torque less than 0.5Nm for smaller blinds and at very low torque (say, less than 0.3 Nm) when coupled with an adjustable spring to provide a well-balanced spring roller blind. Furthermore, embodiments of the present invention stem from the realisation that a motor can be kept stationary, located inside the clutch, effectively creating a clutch shaped motor which can be retrofitted to existing components of roller blind systems, either with or without an adjustable spring as required by the size of the roller blind.

[0036] Advantages provided by the present invention comprise the following:

• fully self contained - fits directly into the cylinder of a spring assisted blind with no need for a matched crown/drive wheel as per prior art tubular motors,

• no clutch needed,

• low torque,

• relatively long battery life,

• improved safety by the omission of control chains,

• can be used on large blinds (such as blinds of up to 4mtr / 13 ft wide),

• the motor looks like a clutch;

• comparatively small,

• relatively inexpensive to manufacture

• can be retrofitted to entire size range of tubes and systems of the prior art by virtue of the shared, common componentry (such as clutch tube adapters and brackets).

[0037] Further scope of applicability of embodiments of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the disclosure herein will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Further disclosure, objects, advantages and aspects of preferred and other embodiments of the present application may be better understood by those skilled in the relevant art by reference to the following description of embodiments taken in conjunction with the accompanying drawings, which are given by way of illustration only, and thus are not limitative of the disclosure herein, and in which:

FIG. 1 illustrates a motor system according to the present invention for use in a spring assisted blind in an assembled view (FIG. 1a) and in an expanded view (FIG. 1 b) to more clearly show the parts. FIG. 1 c illustrates in a partly expanded view, the electrical connection between the batteries and the motor 7;

FIG. 2 illustrates another embodiment of a motor system according to the present invention in an assembled view (FIG. 2a) and in an expanded view (FIG. 2b) to more clearly show the parts. The embodiment shown in FIG. 2 has just one spring, compared with the embodiment shown in FIG. 1 that has 3 springs.

FIG. 3 illustrates a cylinder for use with a battery pack and the motor system of FIG. 1 or FIG. 2;

FIG. 4 illustrates a wand suitable for controlling the motor system of FIG. 1 ;

FIG. 5 illustrates operation of the wand of FIG. 4 for controlling the motor system of FIG. 1 to lower or raise a roller blind to a desired position.

FIG. 6 illustrates in further detail a preferred embodiment of the wand of FIG. 4

FIG. 7 illustrates a motor system of the prior art for use in a spring assisted blind in an expanded view to more clearly show the parts; List of Parts (Present Invention)

1 Motor head 2 End plate

1 b Boss

3 Fixing screws

5 Circuitry

7 Tubular Motor

7a Drive spindle

7b Pins

7c Tubular body

9 Motor housing

9a First part of the motor housing

9b Second part of the motor housing

9c Recesses

11 Circular spring(s)

1 1 a, 1 1 b Spring tang

13 Control cover 14 End housing

13a, 13b Control sectors 14a, 14b Control sectors

13c Recess

15 Clutch housing

17 Clutch housing adaptor 18 Cir-clip

21 Wand 22 Hook

23 Slide controller 24 Slider

25 Cylinder 26 End cap for cylinder

28 Electrical wires

29 Cylinder end adaptor 30 Battery contacts

31 Motor contact rings

51 Blind fabric 52 Weight

54 Top limit position (of blind fabric)

55 Bottom limit position (of blind fabric) 56 Variable resistor

57 Top limit of slider position 58 Bottom limit of slider position

A Maximum length of travel of the slider B Maximum travel distance of blind fabric C Travel distance of slider to P D Travel distance of blind fabric to P

P Desired position

List of parts (Prior Art - FIG. 6)

41 Cylinder 42 Drive wheel

43 Gear box 44 Brake

45 Motor 46 Circuitry

47 Crown 48 Collar

49 Motor head 50 End plate

DETAILED DESCRIPTION

Prior art motors

[0039] Conventional tubular motors for roller blinds are stationary. In use they rotate, a drive wheel which in turn rotates the cylinder to extend or retract a sheet of fabric. The proximal end of the cylinder is supported by a crown member that keys into the profile of the cylinder and rotates in unison with the rotating collar of the motor.

[0040] They are typically plugged into a battery pole, or a transformer, or a solar panel. Some also operate on mains power but are physically larger.

Present invention

[0041] FIG. 1 a illustrates the motorised system of the present invention which is suitable for a spring assisted roller blind. When assembled, it substantially resembles a roller blind clutch. In use, the clutch housing 15 is inserted into one end of a cylinder (not shown in this view) on which blind fabric is wound.

[0042] FIG. 1 b depicts the motorised system of FIG. 1a expanded so that the parts can be more easily seen. Specifically, FIG. 1 b shows a motor 7 having a tubular body 7c and a projecting drive spindle 7a at a first end, the tubular body 7c being housed within the two parts 9a, 9b of a motor housing 9. Circuitry 5 in the form of a circuit chip is also located within the motor housing 9 adjacent the second end of the tubular motor 7. The first end of the tubular motor 7 includes three pins 7b which are received in corresponding holes 9c in the collar of the motor housing. The other end of the motor housing is keyed into the motor head 1 to which an end plate 2 is affixed by screws 3.

[0043] In use the bearing is held by a bracket fixed to a wall or other architectural structure. In this manner the tubular motor 7 and motor housing 9 are fixed and do not rotate when the drive spindle 7a rotates.

[0044] The tubular motor 7 and motor housing 9 are encircled in this embodiment by one circular spring 1 1 of the bidirectional spring clutch. The spring clutch further comprises a control cover 13 having two control sectors 13a, 13b. Tangs 1 1a at the ends of the circular spring 11 are received between the two control sectors 13a, 13b and during use of the spring clutch the tangs 1 1a impinge against the edges of the control sectors 13a, 13b. In this embodiment the clutch comprises one spring, having two tangs but it will be readily apparent to the person skilled in the art that more springs and tangs can be used in this type of clutch.

[0045] The drive shaft 7a of the tubular motor 7 passes through a correspondingly shaped recess 13c in the collar of the control cover 13 and is secured by a cir-clip 18 so that the control cover 13 is caused to rotate as the drive shaft 7a rotates. The control cover 13 conforms to the internal cross-sectional shape of the clutch housing 15 so that the control cover 13 is also caused to rotate along with the cylinder in which it is located.

[0046] The spring clutch prevents fabric from unrolling from the cylinder under the fabric's own weight, or the counter-balance force created by the spring. In this embodiment the circular clutch springs 1 1 operate as the brake against the weight of the blind fabric as it unwinds and extends from the cylinder. This is in contrast to analogous systems of the prior art (as depicted in FIG. 4) which typically include an electromagnetic disc brake which separately attaches to the spindle shaft. (There is no clutch in the prior art)

[0047] The clutch housing 15 terminates at a clutch housing adaptor 17 that fits a correspondingly shaped adaptor 27 in one end of the cylinder 25. FIG. 2 illustrates the cylinder 25 in which batteries (not shown) are enclosed between the adaptor 29 and end cap 26.

[0048] FIG. 1c illustrates in a partly expanded view, the electrical connection between the batteries and the tubular motor 7. Battery contacts 30 are located adjacent the clutch housing adaptor 17 and cylinder end adaptor 27 such that they make electrical connection with the batteries. Two wires 28 pass from the battery contacts 30, along longitudinal channels of the clutch housing 15 to the motor contact rings 31 which are in electrical contact with the tubular motor 7.

[0049] In this manner, electrical connection is made and between the batteries and the tubular motor 7 and motive power is transferred from the tubular motor 7 directly to the cylinder on which the fabric of a spring roller blind is wound. The torque required to rotate the cylinder is low. Optimally, the system of the present invention is coupled with an adjustable spring to further reduce the torque and enhance the balanced of a spring assisted roller blind.

[0050] In this configuration, the system of the present invention effectively creates a clutch shaped motor. This configuration is advantageous because it matches the shape of existing clutches used for roller blinds and can thus be retrofitted to existing roller blind systems.

[0051] FIG 2a illustrates a further embodiment of the motorised system of the present invention; FIG. 2b depicting the motorised system of FIG. 2a in an expanded view so that the parts can be more easily seen. In this embodiment of the present invention, the tubular motor body includes an end housing 14, having two control sectors 14a, 14b. In this embodiment the spring clutch has a single spring 1 1 having tangs. The spring 11 at least partly resides within the end housing 14 and the spring tangs 11a, 1 1 b interact with control sectors 14a, 14b of the end housing.

[0052] FIG. 3 illustrates a cylinder for use with a battery pack and the motor system of FIG. 1 or FIG. 2. [0053] FIG. 4, FIG. 5 and FIG. 6 illustrate a wand 21 for controlling the motor system of FIG. 1. The wand 21 is removably connected by a hook 24 to the boss 1a of the bearing 1 associated with the motorised system of the present invention. A wand 21 is particularly preferred as a replacement for control means of the prior art such as chains and cords which pose a significant choking and injury risk to children.

[0054] The wand 21 includes a manual slider 24 associated with a slide controller 24, the slider 24 sliding longitudinally along part of the wand 21 at the touch of a user finger, to control the position of the blind fabric 51 and weight bar 52 which is wound and unwound from cylinder 25 by the motorised system of the present invention. Moving the slide 24 in a first direction causes extension of the fabric as the motor rotates the cylinder 25 in a direction that unwinds the fabric 51. Moving the slide 24 in a second, opposite direction causes retraction of the fabric 51 as the motor rotates the cylinder 25 in the opposite direction causing the fabric 51 to be wound onto the cylinder 25.

[0055] Within the circuit chip 5, circuitry is provided to facilitate communication between the slider 24 and the motor of the present invention. After the desired top limit position 54 and bottom limit position 55 of the blind fabric 51 has been set, the rolling up and down of the roller blind fabric 51 is controlled by a variable resistor 56. Once the circuitry is programmed with the maximum and minimum distance of fabric travel (B), the blind can be made to stop and any position (P) corresponding to the slider 24 position. The output resistance of the variable resistor 56 varies with the movement of the slider 24 on the slide control 23.

[0056] When the slider 24 moves a distance (C) to a desired position (P), the variable resistor 56 outputs a voltage proportional to the value of its total resistance (C/A%) to the slide controller 23. The slide controller 23 then sends a drive signal to the motor 7, causing the motor 7 to turn clockwise or counter-clockwise. The motor 7 causes the blind fabric 51 to extend or retract a distance D to the position P which is the percentage distance of the full travel distance B of the roller blind 5 (D/B%) and is the same as the percentage position of the slider 24. When the slider 24 moves to the top limit of its position 57 or bottom limit of its position 58, the blind fabric 51 will be retracted or extend to the respective top position 54 or bottom limit position 55. [0057] Thus, distance travelled by the slider 24 is in proportion to the distance travelled by the blind fabric 51 , thus facilitating intuitive use.

[0058] In an alternative embodiment the circuit chip 5 include a circuit card to enable wireless control using a compatible device in one or more communication protocols such as Zigbee, WiFi, Infrared data Association (IrDA), Bluetooth, ultra-wideband (UWA) and Z-wave.

[0059] Prior Art: FIG. 7 is included for comparison and depicts a typical roller blind motor system of the prior art as referred to above, having a small tubular motor 45 which has an output shaft that rotates, causing concomitant rotation of the cylinder on which the blind fabric is wound.

[0060] The motor system is located at one first end of the cylinder 41 and in addition to the tubular motor 45 the system comprises an electromagnetic disc brake 44 which separately attaches to a gear box 43. The system is controlled by circuitry 46.

[0061] It is to be understood that the specific devices and processes illustrated in the attached drawing, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. Additionally, unless otherwise specified, it is to be understood that discussion of a particular feature of component extending in or along a given direction or the like does not mean that the feature or component follows a straight line or axis in such a direction or that it only extends in such direction or on such a plane without other directional components or deviations, unless otherwise specified.

[0062] While this invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modification(s). This application is intended to cover any variations uses or adaptations of the invention following in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth.

[0063] As the present invention may be embodied in several forms without departing from the spirit of the essential characteristics of the invention, it should be understood that the above described embodiments are not to limit the present invention unless otherwise specified, but rather should be construed broadly within the spirit and scope of the invention as defined in the appended claims. The described embodiments are to be considered in all respects as illustrative only and not restrictive.

[0064] Various modifications and equivalent arrangements are intended to be included within the spirit and scope of the invention and appended claims. Therefore, the specific embodiments are to be understood to be illustrative of the many ways in which the principles of the present invention may be practiced. In the following claims, means-plus-function clauses are intended to cover structures as performing the defined function and not only structural equivalents, but also equivalent structures.

[0065] "Comprises/comprising" and "includes/including" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. Thus, unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 'comprising', 'includes', 'including' and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

Claims

1. A motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

(iii) a rotatable cylinder for winding a sheet of blind fabric.

2. A motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body, an end housing and a drive spindle,

(ii) a bi-directional spring clutch operative to engage the tubular motor in one of two modes, the first mode being to frictionally engage the motor end housing in a first direction of movement, and a second mode being to disengage the motor end housing,

(iii) a rotatable cylinder for winding a sheet of blind fabric.

3. A motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

4. A motorised system for a spring assisted roller blind, the system comprising;

(i) a motor having a tubular motor body, and end housing and a drive spindle,

(ii) a bi-directional spring clutch,

5. A motorised system for a spring assisted roller blind, the system comprising:

(i) a motor having a tubular motor body and a drive spindle,

(ii) a bi-directional spring clutch having, one or more springs encircling the end housing, the springs including tangs, a control cover including at least two control sectors for interaction with the tangs, a clutch housing enclosing the one or more springs and the control cover,

6. A motorised system for a spring assisted roller blind, the system comprising: (i) a motor having a tubular motor body, an end housing and a drive spindle, ) a bi-directional spring clutch having, one or more springs associated with the end housing the tubular motor body, the springs including tangs, the end housing including at least two control sectors for interaction with the tangs. a clutch housing enclosing the motor,

7. A motorised system according to any one of the previous claims in operative connection with an adjustable spring of a spring assisted roller blind.

8. A motorised system according to claim 7 wherein the adjustable spring is a torsion spring comprising coils and having a longitudinal axis, a first spring end and a second spring end and a dampener that can be located at a predetermined length along the longitudinal axis of the torsion spring.

9. A motorised system according to any one of the preceding claims which further includes a wand having a manual slider for controlling operation of the motor.

10. A manual slider for control of a spring assisted blind, wherein the distance of linear movement of the manual slider is proportional, to the linear distance of movement of the blind.

1 1 . A motorised system according to claim 9 that further comprises: a variable resistor operable in response to the slider, the variable resistor having an output voltage proportional to movement of the slider between a first slider limiting position and a second slider limiting position, and wherein, in response to the output voltage, a drive signal from a slide controller causes the motor to turn the rotatable cylinder and move the sheet of blind fabric correspondingly between the first blind limiting position and second blind limiting position.