WO2004040080A1

WO2004040080A1 - Screen winch positioning

Info

Publication number: WO2004040080A1
Application number: PCT/AU2003/001309
Authority: WO
Inventors: Mark Snyders
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-10-29
Filing date: 2003-10-07
Publication date: 2004-05-13
Anticipated expiration: 2005-04-29
Also published as: AU2002952322A0

Abstract

A screen (1) is connected by a member (5) to a traveller (13) moveable vertically along an upright mast (6) by operation of a winch permanently sited inside a cowling (10) at the upper-end portion of the mast. A linkage provided by two arms (16) connects the screen (1) to respective end portions of a support (31) extending horizontally above the cowling (10). The support (31) carries a solar panel (18) and lamps (22) energised by batteries inside the cowling (10) which are rechargeable from the solar panel (18). The arms (16) guide the screen (1) during its vertical movement along the mast (6) so that it translates from the horizontal position illustrated to a vertical position alongside the mast when the traveller (13) is lowered by the winch to its lowermost position on the mast. A safety wire (30) is provided between the upper end of the mast (6) and the screen (1).

Description

SCREEN WINCH POSITIONING

Field of the invention

THIS INVENTION relates to a relatively large screen which is capable of being moved along a guide such as a mast or a wall-mounted vertical bar or rail, between a raised position at which it extends horizontally above a space to be protected from ambient conditions such as an overhead sun, and a lowered position at which it is arranged substantially vertically alongside the guide with one edge close to the ground. A mechanism attaches the screen to the guide and guides its movement between its raised and lowered positions. The mechanism conveniently takes the form of a linkage which is pivoted at one end to an intermediate portion of the screen and is pivoted at the other end to the upper portion of the guide. The axes of the two pivots extend parallel to one another. A traveller on the guide is attached to an intermediate portion of the edge of the screen extending alongside it. The action of moving the traveller along the guide is thus to raise and lower the screen.

State of the art

In my copending International Patent Application No. PCT/AU02/00607, hereby inserted by way of reference I have described in detail and claimed two forms of screen support assembly operating as described above. In both forms the screen is moved along the upright guide by a manually-operated winch is manually operated and mounted on the traveller so as to participate in its movement. As the screen may be large, its weight can be considerable and a substantial amount of effort is required to operate the winch. Also the operator must follow with his or her arm it during its movement up the guide which suitably takes the form of a free-standing mast.

Object of the invention

An object of this invention is to provide an improved screen support assembly of the type described above. The invention

A screen support assembly comprises, in accordance with the present invention, an upright guide carrying a screen capable of being moved along the guide between a raised position at which it extends horizontally above a space to be protected from above, and a lowered position at which the screen is supported substantially vertically alongside the guide with one edge close to the ground, a drive unit operable to move the screen between its raised and lowered positions, a traveller attached to an intermediate portion of said one edge and moved along the guide by operation of the drive unit, a connection between the traveller and said one edge of the screen and which allows the screen to move between its two positions with movement of the traveller along the guide, and a linkage connected between an upper portion of the guide and the screen and which guides the screen between its two positions during vertical movement of the traveller along the guide, characterised in that the drive unit is positionally fixed with respect to the guide.

5 Preferably the guide takes the form of a mast. However it may take the form of a vertical rail or rails capable of being attached to a wall and along which the traveller or travellers can move. Suitably the winch is fixed close to the top of the guide and may be attached to the traveller by, for example, a cable, or by a vertical lead-screw rotated by the drive unit and passing through an opening in the traveller such as an 0 internally threaded collar which moves vertically along the lead-screw with operation of the drive unit.

Advantages of the invention

As the drive unit position is fixed, it may be electrically-operated, as flexible electric wiring allowing the winch to move up and down the mast is now not necessary. It 5 will be recognised that trailing electrical wiring alongside the guide could be a source of danger tϋ the public. Thus the simple step of fixing the position of the drive unit with respect to the mast avoids this problem.

Preferred features of the invention

Preferably when using an electrically-operated winch, it has an associated brake or _n clutch which automatically comes into play when power is switched off the winch, thereby retaining the screen at a chosen tilt. This is not necessary when a lead- screw is used to move the screen. A second stand-by brake may be located in the traveller to prevent it from descending when there is no tension in the winch wire.

An advantage of having the drive unit at the upper end of the mast, is that it is out of the reach of small children and an the electrical power cable used to supply electricity to the winch can also be used to power other equipment at the upper end-portion of the guide, such as a security camera, and/or sound and lighting equipment.

In the preferred form of support assembly, a self-contained electrical power unit is used at the top of the mast. It may, for example, comprise a re-chargeable battery or batteries, having associated one or more solar panels conveniently provided on top of the guide and connected to re-charge the battery or batteries.

Suitably a casing on top of the mast is used to prove a solar panel and one or more loudspeakers and an adjacent electronic equipment such as an amplifier and receiver. The loudspeakers may be oriented to direct music downwards beneath the screen. Likewise, a lighting system may be associated with the underside of the solar panel casing to provide light beneath the screen.

The assembly conveniently has a controller which may be manually operated and is suitably located on the mast above the head height of a child. Likewise a hand-held remote controller device may be provided to enable an operator to control screen tilt and rotation in the horizontal plane, and the light and/or sound facilities while seated beneath the screen.

When the guide takes the form of a free-standing mast, the mast upper portion may be rotated with the support assembly about axis of the lower portion. This may be achieved by providing a bearing between upper and lower mast portions. A ring with arcuately-spaced apertures conveniently surrounds the bearing. A releasable detent pin associated with the apertures is biased to locate selectively in any one of them to hold the screen in a chosen rotational position to which it is moved. Extracting the pin from a particular aperture can be effected mechanically and a pull cord may be used to rotate the screen to a new position. The detent pin may the be re-engaged with the ring of apertures. Such an arrangement can be used with an electrically operated drive unit or a manually operated one.

Introduction to the drawings

The invention will now be described in more detail, by way of example, with reference to the accompanying diagrammatic drawings, in which:-

In the drawings

FIGURE 1 is a side view of a mast-supported screen in its overhead position:

FIGURE 2 is a front elevation of figure 1 ;

FIGURE 3 is a plan view of figure 1 ;

FIGURE 4 is a view corresponding to figure 1 but showing the screen in its lowered position;

FIGURE 5 is a front elevation corresponding to figure 2 but showing the screen in its lowered position;

FIGURE 6 is a plan corresponding to figure 3 but again shows the screen in its lowered position;

FIGURE 7 is a rear elevation of the screen in its lowered position ; and,

FIGURE 8 is a perspective view of the raised screen of figure 1 .

Description of preferred embodiment

Figure 8 shows an elevated rectangular screen 1 and its associated support assembly 2. The screen illustrated is made from parallel reeds which allows air to circulate through it, as shown more clearly in figure 3, and its shape is gently undulating as shown more clearly in figure 2. Its shape is maintained by four parallel sinuous bars 4 shown clearly in figure 7 and the centre two of which are arranged close to one another. The bars 4 are held in a spaced parallel relationship by being rigidly attached to three, equi-spaced, load bearing pipes 5. Other constructions of screen may also be used. For example it may be woven and may be covered by flexible overlapping and preferably transparent sheets or membranes which protect the area beneath the screen from rain and which yield in their overlapping regions to allow wind to pass through the screen.

As shown in figure 8, the screen support assembly shown generally at 2 is provided with a vertical mast 6 having a base 7 which is bolted or otherwise mounted securely on a concrete plinth (not shown) to provide a stable support for it. The upper end-portion 8 of the mast is inclined away from the screen 1 and supports a casing 10 containing re-chargeable batteries (not shown) and an electrically-driven winch and associated gearbox (also not shown). The casing and its contents can rotate around the vertical axis of the mast by way of a bearing 11 which is located between the vertical mast 6 and the inclined upper portion 8. The bearing is encircled by a ring (not shown) having arcuately-spaced apertures. A detent pin, also not shown, located in the base of the casing is spring-biased to engage selectively in the apertures to hold the screen in a chosen position around the mast axis. A spring-tensioned device, also not shown, is used to disengage the pin from an aperture. A cord attached to the support assembly may then be used to rotate it horizontally about the bearing. When a new position for the screen is found, the spring-tensioned device is released and the detent automatically re-engages with a different aperture to hold the screen in its new position.

A winch wire 12 is attached at its lower end to a traveller 13 which embraces the mast 6 and is attached by a pivot 14 to the centre of the three rigid pipes 5 at its end which extends beyond the edge of the screen 1 , as clearly shown in figure 8. A linkage, generally shown at 15 in figure 1 , connects the top of the upper portion 8 of the mast to approximately the mid-portions of the outermost two pipes 5. The linkage 15 comprises a pair of divergent arms 16 which at their lower ends are connected by pivots 17, apparent from figure 7, having aligned pivotal axes which are horizontal and arranged at right angles to the longitudinal axes of the pipes 5 to which they are attached. The arms 16 converge upwardly towards one another and, at their upper ends, are journalled at 31 to turn about a common horizontal axis which is parallel to the axes at the lower ends of the arms 16. The journals 31 at the upper ends of the arms 16 are located at the opposite ends of a horizontally- elongated second casing 18 of lenticular vertical section, as is clearly shown in figures 1 and 5. A resiliently-tensioned safety wire 30, shown in figure 8, lies in the same sloping plane as the arms 16 and permanently attaches the outer end of the centre pipe 5 of the screen, to the upper end of the mast. Tne wire 30 extends Q midway between the two arms 16. Uncontrolled collapse of the screen is resisted by the safety wire and also by a brake in the traveller which grips the mast when tension in the winch wire disappears.

The second casing 18 is arranged at a level above and behind the screen 1 when in its elevated position, as shown in figure 1 , and can be tilted around the horizontal 5 axis of the axially-aligned journals 31 to catch the maximum sunlight. The area of the upper surface 20 of the second casing 18 supports a solar panel used to generate electricity to re-charge the batteries housed in the cowling 10.

The underside of the casing 18 is provided with a pair of spaced loudspeakers 22, shown in figure 8, arranged to direct sound downwards where required. An amplifier (not shown) associated with the loudspeakers is mounted between them inside the casing 18, and is powered by the re-chargeable batteries. Likewise lights (not shown) can be provided at the ends of the casing 18 to direct light downwardly to illuminate a required area beneath the elevated screen. Thus the assembly can provide sound and light to the area beneath the elevated screen. A security camera _- also powered by the batteries may also be located on the underside of the casing 1 8.

Because the winch is permanently located at the top of the mast 6 it is out of the way of playing children. Also no visible electrical cables are used which could provide a risk or be easily damaged. The assembly described is self-powered with electricity but provision may also be made for providing external power to it by way of electrical cabling led up through the interior of the mast 6. Manual control for the electrical equipment may be provided by an overhead switch panel provided on the underside of the casing 10. Remote control may also be effected by the use of hand-held controller (not shown) operable by a person beneath the screen.

The mechanical operation of the support assembly is described in detail in the specification of my co-pending International Patent Application No. PCT/AU02/00607 hereby inserted by way of reference.

Operation of preferred embodiment

In outline, the assembly shown in the drawings of the present application operates as follows.

The screen of figure 1 is lowered by arranging for the winch to progressively unwind the winch wire from the associated drum so that the traveller slides gradually down the mast. The screen is thereby tilted about the lower end of the pivot points 1 7 and the links 15 simultaneously rotate about their pivots 31. Thus the screen moves progressively from the position shown in figure 1 towards the position shown in figure 4. As the axis of the pivot points 31 lies behind the mast 6, the final descent of the screen is accompanied by a movement of the upper end of the screen towards the mast 6. Because of the shape of the screen, the mast nests within the central undulation of the screen as is clearly apparent from the plan view ^■ of figure 6. The traveller 8 is now at the foot of the mast.

To raise the screen from the position shown in figure 4, the winch is operated to lift the traveller up the mast. The components of the screen described immediately above then move in the opposite directions to that occurring during screen lowering, until the screen is once again at the fully elevated position shown in figure 1. Although the screen illustrated in the accompanying drawings is rectangular, it may have any other desired shape. Modifications to the preferred embodiment

In some cases it may be preferred to use a manually-operated drive unit at the upper end of the guide, in place of an electrically-operated one. The unit is then provided with a socket to receive a spigot located at the upper end of a long operating pole having a cranked handle at its lower end. To operate the unit the spigot is manually engaged with the socket and the pole is then turned by the handle at its lower end. When the screen has been tilted to a new position, the i spigot is disengaged from the socket and the pole can be^' stored at a safe location.

The action of inserting the spigot into the socket also automatically disengages a locking device on the drive unit which prevents it from turning unless the spigot is in the socket. The risk of small children causing inadvertent operation of the drive unit is thus avoided.

Claims

Claims:

1 . A screen support assembly comprising an upright guide carrying a screen capable of being moved along the guide between a raised position at which it extends horizontally above a space to be protected from above, and a lowered position at which the screen is supported substantially vertically alongside the guide with one edge close to the ground, a drive unit operable to move the screen between its raised and lowered positions, a traveller attached to an intermediate portion of said one edge and moved vertically along the guide by operation of the drive unit, a connection between the traveller and said one edge of the screen and _Q which allows the screen to move between its two positions with movement of the traveller long the guide, and a linkage connected between an upper portion of the guide and the screen and which guides the screen between its two positions during vertical movement of the traveller along the guide, CHARACTERISED IN THAT the drive unit is positionaliy fixed with respect to the guide.

5 2. A support assembly as claimed in claim 1 , in which the guide is provided by a freestanding mast.

3. A support assembly as claimed in claim 1 or claim 2, in which the upper end portion of the guide has a positionaliy adjustable casing enclosing a power unit comprising a rechargeable battery or batteries, and an associated solar panel is connected to recharge the battery or batteries.

4. A support assembly as claimed in claim 3, in which the underside of a casing supporting the solar panel is provided with a loudspeaker, and enclosed electronic circuitry located at the upper end of the guide drives an associated loudspeaker system which directs the sound it generates downwardly beneath the screen.

5. A support assembly as claimed in any one of the preceding claims, in which the underside of the solar panel carries a light source.

6. A support assembly as claimed in any one of the preceding claims, in which the drive unit has associated locking device for retaining the traveller at a chosen position on the mast when the unit is not operated.

7. An assembly as claimed in any one of the preceding claims, including a remote hand-held controller, enabling the position of the traveller on the guide and electronic circuitry at the upper end of the guide to be controlled from a remote position.

8. An assembly as claimed in claim 1 or any one of claims 3 to 7, in which the guide comprises a rail or rails supported by a wall.

9. An assembly as claimed in claim 8, in which the guide includes a vertical lead- screw engaged with an aperture in the traveller whereby operation of the drive unit controls the vertical position of the traveller on the lead-screw.

10. An assembly as claimed in claim 1 , claim 8 or claim 9, in which the drive unit is positioned adjacent to the upper end portion of the guide and is manually operable by engagement of an upper end of a displaceable rotatable pole with an opening in the drive unit.