Adjustable covering for architectural openings

Abstract

 A Window covering for mounting adjacent to a window frame, comprising a fixed upper head box having opposite ends, an operating mechanism housed in the head box, lateral guides each at one of the opposite ends of the head box to coextend with opposite lateral sides of a window frame, a flexible covering member, and a retraction mechanism for the flexible covering member having opposite ends extending between the lateral guides and opposite ends of the retraction mechanism being vertically slidably engaged on the lateral guides for travelling movement therealong,wherein the position of the retraction mechanism along the lateral guides is adjustable.

Description

[0001] In present day business, the use of information technology has become a fundamental precondition in the organisation of labour. Office labour now requires almost anybody to be concerned with measures to govern the amount of solar radiation to be allowed in through the windows of a building.

[0002] It would thus be desirable to eliminate reflections on the display screens of computers and thereby to limit glare by solar light. It has been found that the portion of a window that admits the undesirable rays of light varies substantially with the height and that it is not necessary to cover all of the window to achieve a treshold of comfortable illumination in an office space. Sun protection systems adequately dealing with this problem are relatively scarse and in as far as available have been rather complicated, difficult to operate and costly.

[0003] Accordingly it is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art. It is also an object of the present invention to provide alternative structures which are less cumbersome in assembly and operation and which moreover can be made relatively inexpensively. It is also a general object of this invention to improve the quality of life at an office by offering an improved thermal and visual comfort, through an improved balance between the building, the climate and the occupant. It is a more specific object of the present invention to to provide a window covering that optimises the distribution of natural lighting in a. room, while also minimizing light reflections on computer display screens. More in particular it is an object of the window covering according to the invention to allow the user a maximum in flexibility of adjustments, so as to achieve protection against too much light and glare from sunlight while at the same time maintaining an optimum level of natural light.

[0004] To this end the present invention provides a window covering comprising:

a fixed upper head box for housing technical elements,

lateral guides on opposite sides of the head box,

a spring biased roller extending between and vertically slidably engaged on the lateral guides for movement therealong,

a bottom bar, manually possitionable and fixable at different positions along the guides, wherein the position of the roller along the guides is electrically adjustable.

[0005] In this way the blind according to the invention features two mutually independent movements. A first of these movements allows for screening the sunlight at any position of the sun, by extending a flexible sun screening member over a variable trajectory. A second movement sets the height of the extended sun screening member. At the top, between the top of the window opening and the top of the retractable sun screening member, an adjustable area can be set so as to allow natural light into the room.The electrical adjustment can have a motorised operation connected to a system of automatic control. The window covering according to the invention will lead to a better level of thermal and visual comfort and to a better balance between natural and artificial light and thereby result in energy savings on heating, lighting and cooling.

[0006] One possible form of practising the invention will now be described in detail herein below, in reference to drawing figures in which:

Figure 1 is a perspective view showing a window covering according to the invention in use adjacent to a window opening;

Figure 2 is a perspective detail view showing one end of a head box with the window covering in a fully retracted position;

Figure 3 is a perspective detail view of a bottom bar end portion of the window covering of Figure 1, as indicated there at III;

Figure 4 is partial perspective view showing a detail of the fixed head box and roller, with the front cover of the head box removed to show the operating mechanism for raising and lowering the roller;

Figure 4A is a partial perspective view, somewhat similar to Figure 4, showing a modified operating mechanism for raising and lowering the roller;

Figure 5 is a perspective partial view showing the window covering of Figure 1 with the roller in its lowermost position, but with the flexible covering member still in a rolled-up position;

Figure 6 is a view similar to Figure 5, but showing the flexible covering member in a partly unrolled position with the bottom bar latched in an upper position of elevation;

Figure 7 is a view similar to Figure 5 and 6, but showing the bottom bar latched in a lowermost position of elevation;

Figure 8 is a view very similar to Figure 6, but now with the roller in its uppermost position; and

Figure 9 is a flow chart illustrating the various steps for automatically controlling the raising and lowering of the roller.

[0007] Referring first to Figure 1 a window covering 1 is shown in use adjacent to a framed window opening 2. As also shown in Fig. 1 the window covering 1 is in the form of a roller blind and is mounted on a wall surface 3 surrounding the window opening 2. The window opening 2 has a frame with the usual upper and lower horizontal frame members 2a, 2b and opposite vertical side frame members 2c, 2d. The window covering 1 includes an upper head box 4 which is fixed to wall surface 3 in the vincinity of the upper horizontal frame member 2a. The upper head box 4 has first and second end caps 5 and 6, which are connected to support brackets 7 and 8.
Extending downwardly from each end cap 5, 6 is a guide rod 9, 10 respectively, that serve as lateral guides for a blind roller 13. Each of these guide rods 9, 10 extends downwardly for a limited portion of the height of the window opening 2 and is preferably anchored at its lower end by a wall mount attachment 11 The head box 4 houses an operating mechanism that will be derscribed in relation to notably Figures 4 and 9 hereinbelow. Mounted for up and down movement along the lateral guides 9, 10 is a roller 13 onto, or from, which a flexible window covering sheet 15 can be rolled or unrolled, respectively.
Along a lower edge of the flexible sheet 15 extends an elongate bottom bar 17, provided on its opposite longitudinal ends with longitudinally projecting stop pins 19, 20. These protruding pins 19, 20 can be engaged with confronting bottom bar latches 21, 22 to retain the bottom bar 17 in its lowered position. The roller 13 is spring biased for rolling-up the flexible sheet 15. If not retained by the bottom bar latches 21, 22 the flexible screen 15 will move by spring force to a rolled-up position.

[0008] To enable different positions of lowering for the flexible screen, preferably additional bottom bar latches 23, 24 are provided at a suitable location in-between the latches 21, 22 and the fixed head box 4.

[0009] Figure 2 is a perspective detail view of the upper head box 4 as seen from above. The fixed upper head box 4 comprises an attachment profile 25. This attachment profile 25 is closed of at its ends by the end caps 5, 6 as explained in Figure 1 and also forms a unit with the support brackets 7, 8. At the front of the headbox 4 is a removable cover profile 27 which is preferably designed to form a snugly fitting transition between the attachment profile 25 and the bottom bar 17 in its fully raised position. To limit the upward travel of the bottom bar 17 in respect of the roller 13, there is provided a bottom bar stop 29 on at least one longitudinal end of the roller 13, but preferably on both longitudinal ends thereof.

[0010] Figure 3 shows the detail III from Figure 1 on an enlarged scale. As clearly seen in Figure 3 the bottom bar latch 21 has a recess 31 for locating the bottom bar stop pin 19.

[0011] Figure 4 is an enlarged detail of a top left hand corner of the window covering of Figure 1, but with the cover profile of the head box removed to show the internal mechanism. Also in Figure 4 the roller 13 is shown in a somewhat lowered position with respect to the head box 4.
The blind roller 13 has a conventional spring motor for rolling up the screen cover 15. The centrifugal stopping mechanism conventional for such spring roller blinds can be eliminated in view of the bottom bar latches 21, 22, 23, 24. The opposite longitudinal ends of the roller 13 are mounted in roller end mounts, such as end mount 33. As seen in Figure 4 the end mount slidably engages the guiding rod 9 for movement from and to the head box 4 in a vertical direction. The roller end mounts at each opposite end of roller 13 are also suspended by transporting cables 35 and 37 respectively.
Transportation cables 35, 37 can each be wound or unwound from respective winding pulleys 39, 41. These winding pulleys can be driven in each of two opposite directions of rotation by a common drive shaft (not shown but conventional). This common drive shaft is so driven by an electric motor, which can be any suitable type of commercial tube motor. Preferably the motor 43 is of a type as supplied by BECKER-Antriebe GmbH and designated 5/20S, or of a type supplied by Somfy and designated LS40. These motors can be combined with various electrical controls.
To guide the transportation cable 35 from alongside the guiding rod 9 towards and onto the winding pulleys 39, 41 respectively, a suitable number of guide pulleys 45, 47 and 49 are rotatably mounted on the attachment profile 25 of the head box 4. The guide pulley at the second cap 6 (not shown in Figure 4) is similar to guide pulley 45 and generally in a mirror-image arrangement.

[0012] Figure 4A is a partial perspective view, somewhat similar to Figure 4, showing a modified operating mechanism for raising and lowering the roller. The embodiment of Figure 4A provides for a slightly more compact arrangement of components within headbox 4A. End cap 5A, support bracket 7A and guide rod 9A are generally similar to those in the embodiment of Figure 4. The attachment profile 25A mounts the guide pulleys 47A and 48A in a slightly different orientation with respect to winding pulleys 39A and 41A. The headbox 4A in Figure 4A is shown, for clarity, without the transportation cables and without the blind roller suspended therefrom. Without these transportation cablesit is seen that the winding pulleys 39A and 41A each have a stepped core surface 51 and 53, respectively. It has been found that this stepped core surface greatly assists in forming the initial windings of the transportation cables, while preventing succesive windings to become entangled. This is particularly helpful if the guide pulleys (47A, 49A) are positioned close to the winding pulleys (39A, 41A).

[0013] Starting from the positions illustrated in Figures 5, 7 and 8 the bottom bar 17 can be manually engaged with the bottom bar latch 21, or the additional bottom bar latch 23. Also shown in Figures 5 through 8 is that the roller 13 can be moved between a lower most position and a raised position in which it abuts the head box 4. Since the flexible covering sheet 15 is rolled and unrolled from the spring biased roller 13, the up and down movement of the latter is independent from the position of bottom 17. The manually adjustable position of the bottom bar 17 is chosen by persons occupying a windowed room fitted with the window covering 1, in accordance with their preferred comfort. The position of the roller 13 is controlled automatically in response to a predetermined amount of illumination required in the subject room. This proposed arrangement results in a very efficient and convenient window covering product, allowing individual settings for creature comfort, while alleviating the difficult task of administering daylight illumination.

[0014] With respect to Figure 9 there will now be described a suitable control system for automatically raising and lowering the roller 13 in respect of the head box 4 to admit daylight at the top of the window covering 1.

[0015] Step 101 represents the manual action of bringing the bottom bar in an operative position. Step 102 represents the action of starting the automatic operating sequence. Both steps 101 and 102 are not part of the normal operating sequence and are merely represented in Figure 9 for the sake of completeness. The automatic operating cycle is governed by a time interval generator 103, which generates a delay of preferably several minutes of time between subsequent light level measurements to be carried out by the system. The timer 103 initializes the determination in step 104 of the azimuth position of the sun in accordance with the time, date and location to decide whether or not there could be direct sunlight impinging on the window (2 of Figure 1). When there cannot be any direct sunlight, the program progresses to step 105 to measure the level of light available at the window. If the level of daylight does not exceed a first low level (i.e. 15000 lux) then the program proceeds to step 107 in which the roller 13 is moved from its initially raised position to the lowermost position, after which the next measurement and adjustment cycle is awaited. If at step 106 the light level is determined to be higher than the first range, then the program proceeds to step 108, which determines whether the light level falls within a second range (i.e. of 15000-40000 Lux). When this is the case step 109 will adjust the roller to a first intermediate position, higeher than its lowermost position. With a level of light still higher than the second range the program will proceed to step 110, which detects whether the light level falls within a third range (i.e. within 40000 to 60000 Lux). When this is the case step 111 will adjust the roller to a second intermediate position, higher than the first intermediate position.

[0016] With the light level still higher than the third range (i.e. over 60000 lux) the roller will remain in its initial upper-most position.

[0017] When step 104 detects that there could be direct sunlight the program proceeds to step 112, for measuring the amount of light impinging on the window (2 in Figure 1). If the amount of light falling on the window is within a first range (i.e. 0-15000 lux), step 113 directs the program to step 114, which determines the altitude of the sun. If the altitude of the sun is in a first low angle range (i.e. 5-15 degrees) then step 115 adjusts the roller 13 from the initial upper-most to the lowermost position. With the sun at a steeper angle of altitude the program will proceed to step 116, which detects whether the altitude is within a second range (i.e. 15-45 degrees)., When the altitude of the sun does not exceed the second range, then step 118 will adjust the position of roller 13 to a first intermediate position higher than the lowermost position. In case the altitude exceeds the second range then the program will proceed to step 117, which adjusts the roller to a second intermediate position, higher than the first intermediate position.

[0018] If step 113 determines that the level of light exceeds the first range the program proceeds to step 119. Step 119 determines whether the level of daylight is within a second range (i.e. of 15000-40000 lux). If the amount of light falling on the window is within this second range, step 119 directs the program to step 120, which determines the altitude of the sun. If the altitude of the sun is in a first low angle range (i.e. 5-15 degrees) then step 121 adjusts the roller 13 from the initial upper-most to the lowermost position. With the sun at a steeper angle of altitude the program will proceed to step 122, which detects whether the altitude is within a second range (i.e. 15-45 degrees). When the altitude of the sun does not exceed the second range, then step 124 will adjust the position of roller 13 to a first intermediate position higher than the lowermost position. In case the altitude exceeds the second range then the program will proceed to step 123, which adjusts the roller to a second intermediate position, higher than the first intermediate position.

[0019] If step 119 determines that the level of light exceeds the first range the program proceeds to step 125. Step 125 determines whether the level of daylight is within a third range (i.e. of 40000-60000 lux). If the amount of light falling on the window is within this third range (i.e. 40000-60000 lux), step 125 directs the program to step 126, which determines the altitude of the sun. If the altitude of the sun is in a first low angle range (i.e. 5-15 degrees) then step 127 adjusts the roller 13 from the initial upper-most to the lowermost position. With the sun at a steeper angle of altitude the program will proceed to step 128, which detects whether the altitude is within a second range (i.e. 15-45 degrees). When the altitude of the sun does not exceed the second range, then step 130 will adjust the position of roller 13 to a first intermediate position higher than the lowermost position. In case the altitude exceeds the second range then the program will proceed to step 129, which adjusts the roller to a second intermediate position, higher than the first intermediate position.

[0020] If step 125 determines that the level of daylight exceeds the third range (i.e. exceeds 60,000 Lux), then the roller 13 will be kept in its initial upper-most position, or be moved thereto if it was in any of the lowered positions due to a previous adjustment.

[0021] Although the steps of the program have been described in one particular order, the skilled person will recognise that the order of measuring daylight level and sun altitude can be reversed. Similarly the determination of ranges, now shown in increasing value, would be equally effective if arranged in a decreasing order. The flow chart of Figure 9 only serves to illustrate a suitable array of steps to automatically control the admittance of daylight by altering the position of the top of the covered area with respect to the top of the window opening.

[0022] In this regard it should also be clear that the roller 13 and the bottom bar 17 can be in an inversed arrangement, wherein the bottom bar 17 is at the to and the roller 13 at the bottom of the window covering.

[0023] It is thus believed that the operation and construction of the present invention will be apparent from the foregoing description. The term comprising when used in this description or the appended claims should not be construed in an exclusive or exhaustive sense but rather in an inclusive sense. Expressions such as: "means for ...". should be read as: "component configured for ..." or "member constructed to ..." and should be construed to include equivalents for the structures disclosed. The use of expressions like: "critical", "preferred", "especially preferred" etc., is not intended to limit the invention. Features which are not specifically or explicitely described or claimed may be additionally included in the structure according to the present invention without deviating from its scope.

[0024] The invention is further not limited to any embodiment herein described and, within the purview of the skilled person, modifications are possible which should be considered within the scope of the appended claims. Equally all kinematic inversions are to be considered within the scope of the present invention.

[0025] Reference to either axially, radially or tangentially if used in the above is generally in relation to rotatable or cylindrical bodies of elements described.

[0026] Where in the above reference is made to longitudinal or lateral this is in reference to the length or width directions respectively of elements which have a generally oblong appearance in the accompanying drawings. This interpretation however has only been used for ease of reference and should not be construed as a limitation of the shape of such elements.

[0027] Expressions, such as right, left, horizontal, vertical, above, below, upper, lower, top, bottom or the like if used in reference to the construction as illustrated in the accompanying drawings are relevant to the relative positions and in a different orientation of the construction should be interpreted in accordance with comparable relative positions.

Claims

1. Window covering for mounting adjacent to a window frame, comprising:

a fixed upper head box having opposite ends,

an operating mechanism housed in the head box,

lateral guides each at one of the opposite ends of the head box to coextend with opposite lateral sides of a window frame,

a flexible covering member, and

a retraction mechanism for the flexible covering member having opposite ends extending between the lateral guides and opposite ends of the retraction mechanism being vertically slidably engaged on the lateral guides for travelling movement therealong,

   wherein the position of the retraction mechanism along the lateral guides is adjustable.

2. Window covering according to claim 1, wherein the flexible covering member is provided with a bottom bar along a lower edge of the flexible covering member opposite to the retraction mechanism.

3. Window covering according to claim 2, wherein the bottom bar is manually positionable and fixable in at least one position of elevation in bottom bar latches.

4. Window covering according to claim 3, wherein the bottom bar is positionable in different positions of elevation as defined by a plurality of bottom bar latches.

5. Window covering according to claim 2, wherein the retraction mechanism includes a roller.

6. Window covering according to claim 5, wherein the roller is spring biased.

7. Window covering according to claim 5, wherein the bottom bar, in a retracted position of the flexible covering member, is covering a front face of the roller.

8. Window covering according to any preceding claim, wherein the retraction mechanism is electrically adjustable.

9. Window covering according to any preceding claim, wherein the lateral guides includes an elongated rod.

10. Window covering according to any preceding claim, wherein the position of the retraction mechanism at the lateral guides is adjustable by automatic control means.

11. Window covering according to claim 10, wherein the automatic control means is responsive to at least one of a light level, an azimuth position and an altidude angle.

Drawing