Patent Application
20080216966
The present invention relates to the field of Venetian blinds. More particularly, the invention relates to a manually operated Venetian blind that can be lowered/raised and tilted effortlessly and speedily by means of a novel, reliable, and cost-effective operating mechanism.
Shading devices have been traditionally used to reduce the area of glazing which is exposed to an influx of solar radiation.
Operable shading devices mounted exterior to windows are designed to control the incoming solar radiation. They may have a complex mechanism which requires maintenance or replacement, or may have an expensive automatic control system.
Other types of shading devices, such as roller shades, curtains or Venetian blinds, are installed within the interior of a building and are adapted to reflect incoming solar radiation back through the window before it can be absorbed and converted to heat. Recently, internal blinds, i.e. Venetian blinds that are arranged in a spaced parallel relationship and are placed between glass sheets in a double glazing unit or between the frames of a double window, have been employed.
Prior art Venetian blinds, must remain in an upright position, such that a longitudinal axis coinciding with each slat is essentially perpendicular to horizontally disposed flooring, during transportation, installation and while in use so that the slats and cords will not be in a state of disarray and be rendered unusable. If the longitudinal axis of the blind arrangement were not in an essentially vertical disposition, some of the blinds would touch the glazing, causing the cords which support the blinds to become entangled.
Venetian blinds are generally provided with at least two ladder braids, the number of ladder braids depending on the length of the slats. Each ladder braid is composed of two outer cords for tilting the slats, an inner cord for raising and lowering the slats, and a plurality of cross ladders. Each of the cross ladders is connected between the two outer cords and supports a corresponding horizontally disposed slat. The outer cords of prior art Venetian blinds, which provide a tilting motion, are directed to the tilting mechanism by means of a spacer placed on the outside of the uppermost slat. As a result, the weight of the slats is concentrated disproportionally more on the spacer and the uppermost slat than on the other slats, causing the slats to change their relative position, or even to fail, over the course of time. The tilting mechanism is usually a gear train that adds to the cost of the blind unit. Also, due to the angle of the cords the blinds cannot completely close and invariably only 75% of the incoming light is blocked.
Concerning the raising and lowering of prior art internal Venetian blinds, the actuation is generally by means of a magnet external to the glazing which linearly translates another magnet imbedded within the raising mechanism. The degree of raising or lowering of the blind is completely dependent on the displacement of the external magnet, and may take up to 2 minutes to raise the blind from a lowered position to a raised position. Due to the configuration of the cord and spacers, the area of the blind is limited to 2 sq. meters. A considerable force must be applied in order to raise the blind.
U.S. Pat. No. 3,702,040 discloses a Venetian blind structure that is adapted to be mounted within the air space of a double glazed sealed window unit. A plurality of elongated slats are pivotally mounted at their ends in a support frame, such that pins which protrude from a wheel secured to the pivot shaft of each slat abut transverse edges of a reciprocable actuating member driven by a gear train and therefore limit the angular position of the slats. The gear train is adapted to tilt the slats, but the Venetian blind structure is not provided with a means to raise or to lower the slats. Also the addition of the gear train adds to the cost of producing and assembling the blind structure.
U.S. Pat. No. 6,059,006 is another actuation device for adjusting the inclination of Venetian blinds arranged inside a double glazing unit. A first magnet is slidingly movable inside the sealed space of the double glazing unit, in response to the movement of a second magnet, which is located inside a box-like body connected outside the double glazing unit and driven by a cord stretching in a loop between two pulleys and connected to an actuation rod. The first magnet is fixed to a bush which is internally shaped complementarily to the helical profile of a shaft, so that translatory motion of the first magnet results in rotation of the shaft and of vertical adjustment chords to thereby synchronously adjust the inclination of the blinds about a longitudinal axis thereof. The complexity and cost of the apparatus is increased, due to the transmission system, as well as the actuator that is external to the double glazing unit.
U.S. Pat. No. 6,095,223 discloses an actuation unit that includes a magnetic kinematic coupling device which is connected to an electric motor and to a kinematic system for moving an internal Venetian blind. The apparatus of the actuation unit adds to the cost of the Venetian blind.
Other manually operated Venetian blinds mounted in a double glazing unit are disclosed in EP 0 245 811, EP 1 087 095, EP 0 902 155, U.S. Pat. No. 4,685,502, U.S. Pat. No. 4,768,576, US 2003/0089462, and US 2004/0211528.
It is an object of the present invention to provide a Venetian blind assembly which is incorporated in a permanently sealed double glazed window unit.
It is an object of the present invention to provide an internal Venetian blind assembly that provides for the tilting, raising and lowering of the slats.
It is an additional object of the present invention to provide an internal Venetian blind assembly in which means for tilting, raising and lowering of the slats are disposed internally to the double glazed window unit.
It is an additional object of the present invention to provide an internal Venetian blind assembly for which means for tilting, raising and lowering of the slats are manually actuated.
It is an additional object of the present invention to provide an internal Venetian blind assembly for which the tilting, raising and/or lowering of the slats can be reliably completed within approximately 2 seconds.
It is an additional object of the present invention to provide an internal Venetian blind assembly for which means for tilting, raising and lowering of the slats are relatively frictionless and can be easily assembled.
It is an additional object of the present invention to provide an internal Venetian blind assembly in which the means for tilting, raising and lowering of the slats do not incorporate a gear train, a set of pulleys or couplings.
It is yet an additional object of the present invention to provide an internal Venetian blind assembly that can be inverted without resulting in cord entanglement and can be operable immediately thereafter.
It is yet an additional object of the present invention to provide an internal Venetian blind assembly by which the slats may be tilted, raised and lowered while the blind assembly is disposed at an inclination of approximately 45 degrees with respect to the floor.
It is yet an additional object of the present invention to provide an internal Venetian blind assembly that blocks approximately 90% of the incoming light.
It is yet an additional object of the present invention to provide an internal Venetian blind assembly that overcomes the disadvantages of the prior art.
Other objects and advantages of the invention will become apparent as the description proceeds.
One embodiment of the present invention provides a manually operated internal Venetian blind which comprises an arrangement for raising/lowering a plurality of slats. The arrangement comprises:
a) A frame comprising a transversally extending headrail and lower support member, each of which having at least one planar support surface, and two longitudinally extending side members positioned at each transversal end of said blind, said frame being interposed between two glass sheets;
b) A plurality of transversally extending, equally sized slats suspended from said headrail by means of at least two ladder braids, each ladder braid comprising two longitudinally extending outer cords, each of which being disposed laterally outward from a different lateral edge of the slats, and a plurality of laterally extending cross ladders, each cross ladder being connected to the two outer cords and supporting a corresponding slat, wherein two outwardly positioned ladder braids further comprise a longitudinally extending central cord passing through each slat;
c) A transversally oriented slat support disposed underneath said plurality of slats to which each of said ladder braids is affixed;
d) A bearing housing for housing a ball bearing, wherein said bearing housing is secured to the upper longitudinal end of a first side member;
e) A bifurcated bearing block longitudinally displaceable within said first side member which houses a ball bearing;
f) A counterweight longitudinally displaceable within said first side member and integrally formed by a central portion and two outward portions, each of said outward portions being disposed laterally outwardly from said central portion, at least one internal magnet being housed in an outward portion, said bearing block and said counterweight being interconnected;
g) a stabilizer affixed proximate to the upper longitudinal end of said first side member; and
h) a first linearly displaceable actuator disposed outwardly to one of said glass sheets and provided with at least one external magnet in opposed relation to, and at a fixed distance from, said internal magnet which is housed in said counterweight, said external and internal magnets being magnetically coupled,
wherein each central cord is transversally oriented within said headrail, is wound around the ball bearing housed in said bearing housing, is further wound around the ball bearing housed in said bearing block, and the ends of each central cord are affixed to said stabilizer, said stabilizer thereby applying a reactive force to each of the central cords during displacement of said central cords,
said counterweight and said bearing block being longitudinally displaceable upon linear displacement of said first actuator, the displacement of said first actuator being significantly less than the distance to which the longitudinally lowest slat is raised or lowered due to the winding of said central cords around the ball bearing of said bearing block.
The following are definitions for various terms that are referred to herein:
“internal Venetian blind”—a unit comprising a plurality of slats, frame, and operating mechanism, all interposed between two sheets of glass;
“external Venetian blind”—a unit comprising a plurality of slats, frame, and operating mechanism, which is not interposed between two sheets of glass;
“longitudinal”—in the direction between the headrail and lower rail or lower support member, generally denoting the direction to which the plurality of slats are raised and lowered;
“transversal”—in the direction to which the slats extend;
“lateral”—in the direction perpendicular to the longitudinal and lateral directions, in the direction between the two glass sheets of an internal Venetian blind;
“extending”—concerning an element having one side longer than the other side, in the direction of the longer side;
“oriented”—the disposition of a wall or face of an element which coincides with a longitudinally, transversally, or laterally positioned plane; for example, a wall may be longitudinally oriented while being transversally extending;
“inner” and “inwards”—in a direction towards the cavity between the two glass sheets;
“outer” and “outwards”—in a direction away from the cavity between the two glass sheets;
“upper,” “upwards,” and “above”—in a longitudinal direction closer to the headrail;
“lower,” “downwards,” and “below”—in a longitudinal direction away from the headrail;
“front”—in a lateral direction towards a user that manipulates the actuator; and
“rear”—in a lateral direction away from a user that manipulates the actuator.
Preferably, the bearing housing has a laterally oriented base and two parallel, flexible rings which longitudinally protrude from said base, a ball bearing and a pair of plain bearings for supporting and positioning said ball bearing being housed in said bearing housing.
Preferably, the bifurcated bearing block comprises two symmetrical rectilinear sections for housing a ball bearing therebetween, each of said sections being formed of a laterally thicker portion and a laterally narrower portion, said thicker portion being above said narrower portion, each of said thicker portions being formed with a circular recess to receive therein a corresponding bearing flange and an annular portion outwardly protruding from the back of said recess in which a corresponding bearing axle is seated, wherein the narrower portions are mated such that each upper portion is spaced one from the other with only a bearing rim located between said bearing flanges being visible, a hole being bored through said mated narrower portions.
Preferably, a hole is bored through a portion of the central portion of the counterweight longitudinally protruding from said outward portions, said bearing block and counterweight are interconnected by means of a rope tied through the hole bored through said lower portions of said bearing block and through the hole bored through said central portion of the counterweight;
By winding the central cords about the ball bearings housed in the bearing housing and bearing block, respectively, and then affixing the ends of each central cord to the stabilizer, the central cords are subjected to a frictional force significantly less than that of the prior art. While prior art blinds require a full 100% stroke length to achieve a complete raising/lowering of the slats, the displacement of the actuator of the present invention is advantageously only 40% of the distance to which the longitudinally lowest slat is raised or lowered. Consequently, the slats of a blind having a surface area of up to 5 square meters can be lowered or raised effortlessly and speedily.
In one aspect, the outer cords and central cord of each ladder braid is disposed at essentially 90 degrees with respect to the support surface between the headrail and lower rail.
One embodiment of the present invention provides a manually operated internal Venetian blind which comprises an arrangement for tilting a plurality of slats. The tilting arrangement comprises:
a) Frame components comprising a transversally extending headrail and lower support member, each of which having at least one planar transversally oriented support surface, and two longitudinally extending side members positioned at each transversal end of said blind, a frame assembled from said frame components being interposed between two glass sheets;
b) A plurality of transversally extending, equally sized slats suspended from said headrail by means of at least two ladder braids, each ladder braid comprising two longitudinally extending outer cords, each of which being disposed laterally outward from a different lateral edge of the slats, and a plurality of laterally extending cross ladders, each cross ladder being connected to the two outer cords and supporting a corresponding slat, wherein two outwardly positioned ladder braids optionally further comprise a longitudinally extending central cord passing through each slat;
c) Device for tilting said plurality of slats to which two outer cords of a corresponding ladder braid are affixed, each of said tilting devices comprising two laterally oriented sides, a rectangular face perpendicular to said laterally oriented sides, and an annular protrusion transversally extending outwardly from each laterally oriented side, wherein said tilting device is rotatable about a transversal axis coincident with the axis of said annular protrusions, said annular protrusions being rotatably supported by a suitable assembly secured to a support surface of said headrail or said lower support member which is internal to said glass sheets;
d) Means for rotationally driving each of said tilting devices which is internal to said glass sheets; and
e) A linearly displaceable actuator in communication with said driving means,
wherein an outer cord is partially wound around, and tensioned by, a corresponding tilting device during rotation thereof following displacement of said actuator, said outer cord being subsequently longitudinally and laterally displaced, causing uniform tilting of each of said slats.
Several prior art internal Venetian blinds comprise a tilting mechanism disposed in the headrail by which outer cords of a ladder braid are wound around a cylindrical element, which is generally driven by gears, or any other type of transmission in communication with an actuator external to the Venetian blind. Since this cylindrical element is housed within the headrail, the circumference of the cylindrical element is laterally spaced from the lateral periphery of the slats across which the outer cords extend. Spacers placed on the transversal periphery of the uppermost slat are therefore needed to direct the outer cords to the cylindrical element.
In contrast, the tilting device of the present invention is configured such that two outer cords are affixed to a corresponding tilting device by two affixation means, respectively, that retain the cords in an essentially vertical disposition from the headrail to the lower support member. The weight of the slats is therefore more evenly distributed than in the prior art, allowing the slats of a blind having a higher surface area than has been known heretofore to be tilted with greater reliability and without use of a gear train.
When the slats are in a completely open position, the outer cords have equal tension. Upon displacement of the actuator, a first outer cord is partially wound around, and tensioned by, a tensing portion of the tilting device during rotation thereof to a first angular distance, while a second outer cord is slackened. The first outer cord is then drawn upwards and inwards, causing the slats to change their inclination with respect to a horizontal plane. Following additional displacement of the actuator, the first outer cord is further drawn upwards and inwards, causing an additional change in the inclination of the slats, and the second outer cord is drawn downwards. When the slats are in a closed position, the spacing between the two outer cords is at a minimum. During this stage, the tension of the first outer cord is maximum, and this maximum tension further assists in closing the slats by pressing on the top of each slat, thereby increasing the inclination thereof.
The blind may also be provided with an arrangement for raising/lowering the plurality of slats.
In one embodiment, the two outer cords are affixed to a corresponding tilting device by two affixation means, respectively, positioned along the transversal centerline of the rectangular face thereof in such a way that an outer cord contacts one of said two opposed faces when said rectangular face is parallel to said at least one support surface. Each affixation means comprises an aperture bored through the rectangular face and a corresponding nail having radial protrusions, said nail being received in said aperture. The radial protrusions are adapted to press an outer cord onto the wall of the aperture and to thereby retain the pressed portions of the outer cord in a fixed position relative to the rectangular face of the tilting device.
In one embodiment, the tilting device comprises:
a) a core member provided with—
i. two laterally oriented walls;
ii. a convex periphery disposed between, and integral with, said laterally oriented walls in such a way that the axis of said periphery is transversally extending;
iii. a toothed key protruding from, and having a similar curvature as, said periphery;
iv. at least one coaxial protrusion extending transversally from each of said laterally oriented walls, wherein one of said coaxial protrusions extending from a corresponding laterally oriented wall is adapted to receive a D-shaped shaft for driving the tilting device and one of said coaxial protrusions is rotatably supported by a suitably sized opening formed in a cord guide assembly secured to a headrail or lower rail of the blind;
v. two separated coplanar elements defining a rectangular face which truncate said laterally oriented walls and said periphery such that the diameter of said at least one coaxial protrusion is greater than the maximum radial dimension between said periphery and said coplanar elements;
vi. two transversally extending grooves of bilateral symmetry having a rectangular cross section and obliquely oriented with respect to said coplanar elements, each of said grooves being formed at a different lateral side of said at least one coaxial protrusion;
vii. a portion for tensing an outer cord formed between one of said grooves and the corresponding planar element; and
viii. a circumferential, rectangularly shaped recess formed between said toothed key and a corresponding laterally oriented wall;
b) two oppositely oriented wing members which are engageable with said core member, each of said wing members being provided with—
i. a convex shell having a curvature substantially equal to that of the periphery of said core member and being positioned such that the axis thereof is transversally extending;
ii. a first transversal end of said shell formed with two openings so as to define a central shell portion and two peripheral portions and with a lip circumferentially extending along the inner wall of said shell, each of said peripheral portions being considerably thicker than said central portion and being configured to be received within a corresponding groove of said core member;
iii. a second transversal end proximate to said toothed key having a laterally oriented circumferential wall extending between said two peripheral portions along the inner wall of said shell; and
iv. a plurality of radially extending teeth formed in said laterally oriented circumferential wall, each of said teeth being configured with a sufficient length and spacing therebetween so as to abut complementary recessed sharp edge junctions of said toothed key;
wherein said teeth of each wing member retain a corresponding outer cord of a ladder braid of the blind which is placed on the periphery of said core member in pressed relation with said toothed key,
wherein the lip of each of said wing member is adapted to engage a corresponding recess of said core member with a snapping action to prevent detachment of said corresponding outer cord from the tilting device, wherein an outer cord is partially wound around, and tensioned by, a corresponding tilting device during rotation thereof following displacement of a linearly displaceable actuator, said outer cord being subsequently longitudinally and laterally displaced, causing uniform tilting of a plurality of transversally extending slats each of which is supported by at least two ladder braids.
The central and outer cords are received in a cord guide assembly in immobilized engagement with the headrail or lower support member. A partitioned cord guide for separating each cord is secured to, or integrally formed with, a transversally oriented face of the cord guide assembly. The cord guide abuts the wall of an equally sized aperture formed in the support surface of the corresponding headrail or lower support member, thereby preventing movement in the transversal and lateral directions. The cord guide is substantially coplanar with the corresponding support surface.
The present invention is also directed to a linearly displaceable actuator for use in an internal Venetian blind, comprising:
a) An actuator guide mounted by a press fit between a glass sheet of the blind and a frame element of the wall opening in which the blind is placed, a linear track having an arcuate cross section being formed within said actuator guide;
b) An external magnet housing having a body with an inwardly facing cavity for the insertion therein of an external magnet and an L-shaped appendage protruding from said body, said L-shaped appendage being adapted to be slidingly displaceable within said track; and
c) An internal magnet housing positioned within a frame component of said internal Venetian blind, said internal magnet housing being formed with an outwardly facing cavity for the insertion therein of an internal magnet in opposed relation to, and at a fixed distance from, said external magnet, an elongated element parallel to the back of said outwardly facing cavity, a bridge connecting between said elongated element and the back of said outwardly facing cavity, and coplanar abutment plates extending from each of the elongated element and cavity back to such a length that a gap is formed between said abutment plates,
wherein a drive means for tilting or raising/lowering a plurality of slats is in communication with one of said abutment plates, said drive means operable upon displacement of said body.
In one aspect, the external magnet housing is suitable for adjusting the applied magnetic force by changing the number of magnets housed within the magnet retaining compartment.
The present invention is also directed to a driving assembly for a manually operated Venetian blind, comprising:
a) a rotatable cylindrical casing positioned within a headrail or side member of a blind frame, a hole being bored through the periphery of said casing;
b) means for receiving a transversally oriented shaft by which a tilting device of said blind is rotated;
c) an actuator cord fed through said hole bored through the periphery of said driving assembly in such a way that two portions of said actuator cord dangle in disengageable fashion from a diametrically opposite periphery of said casing; and
d) an actuator in communication with said two portions of said actuator cord, wherein said casing and receiving means are an integral non-detachable unit, wherein the tensile force of at least one of said two portions of said actuator cord upon displacement of said actuator is sufficiently high to cause rotation of said driving assembly, whereby to drive said tilting device.
In one aspect, the casing is rotatably supported within the walls of a circular aperture formed within a first longitudinal end of a laterally oriented wall of a side member. The actuator cord is partially wound about a bearing element rotatingly supported by a bearing housing secured to a second longitudinal end of said side member and is fed through a linearly displaceable actuator. The ends of the actuator cord are tied to each other, the driving assembly and the shaft received therein being rotatable in unison upon displacement of said linearly displaceable actuator.
In one aspect, the receiving means is a D-shaped core to which a plurality of ribs radially extend from the inner face of the casing, said core coinciding substantially with the axis of the casing.
The present invention is also directed to an apparatus for the lateral centering of central cords of a manually operated Venetian blind, comprising:
a) A frame comprising a transversally extending headrail and lower support member, each of which having at least one transversally oriented planar support surface, and two longitudinally oriented side members positioned at each transversal end of said blind, said frame being interposed between two glass sheets;
b) A plurality of transversally extending, equally sized slats suspended from said headrail by means of at least two ladder braids, each ladder braid comprising two longitudinally extending outer cords, each of which being disposed laterally outward from a different lateral edge of the slats, and a plurality of laterally extending cross ladders, each cross ladder being connected to the two outer cords and supporting a corresponding slat, wherein two outwardly positioned ladder braids further comprise a longitudinally extending central cord passing through each slat; and
c) A cord guide assembly secured to a headrail or to a lower support member, said cord guide assembly being provided with transversally and laterally oriented walls, a rectangular opening being formed in each lateral wall of said cord guide assembly, at essentially the lateral centerline thereof,
said cord guide assembly being further formed with internal laterally oriented walls extending from a corresponding transversally oriented wall which are suitably configured so as to allow each axle of a bearing element to be rotatingly seated between a pair of said internal laterally oriented walls wherein the axis of said axles is laterally oriented,
said cord guide assembly being further formed with a pair of parallel, transversally extending partitions, the spacing between said partitions being substantially equal to the lateral dimension of said rectangular opening, such that a central cord is transversally fed through said cord guide assembly via said rectangular openings and said partitions,
wherein said partitions are adapted to limit the lateral movement of a central cord fed through said cord guide assembly and in contact with said bearing element when said blind is tilted,
wherein a longitudinal wall of said rectangular opening is adapted to contact a central cord fed therethrough when the blind is completely inverted and to further urge said central cord to the lateral centerline of said cord guide assembly.
The present invention is also directed to a manually operated external Venetian blind, comprising:
a) A frame comprising a transversally extending headrail having a planar transversally oriented support surface;
b) A plurality of transversally extending, equally sized slats suspended from said headrail by means of at least two ladder braids, each ladder braid comprising two longitudinally extending outer cords being disposed laterally outwardly from a different lateral edge of the slats and a plurality of laterally extending cross ladders, each cross ladder being connected to the two outer cords and supporting a corresponding slat, wherein two outwardly positioned ladder braids further comprise a longitudinally extending central cord passing through each slat;
c) A cord guide assembly in immobilized engagement with said headrail comprising a transversally oriented and inwardly positioned face, two longitudinally oriented sides, and two laterally oriented sides, each of said laterally oriented sides being formed with an arcuate opening outwardly separated from said transversally oriented face;
d) A device for tilting said plurality of slats to which two outer cords of a corresponding ladder braid are affixed, each of said tilting devices comprising two laterally oriented sides, a rectangular face perpendicular to said laterally oriented sides, and an annular protrusion transversally extending outwardly from each laterally oriented side, wherein said tilting device is rotatable about a transversal axis coincident with the axis of said annular protrusions, said annular protrusions being rotatably supported by a corresponding annular opening of said cord guide assembly;
e) A transversally extending D-shaped shaft received in an annular protrusion of each of said tilting devices, two adjacent tilting devices being interconnected by means of one of said shafts;
f) a driving assembly having a cylindrical casing in which a hole is bored through the periphery thereof, and means for receiving one of said shafts;
g) an actuator cord fed through said hole bored through the periphery of said driving assembly in such a way that two ends of said actuator cord dangle in disengageable fashion from a diametrically opposite periphery of said driving assembly; and
h) a cord lock for securing each central cord and thereby retaining the plurality of slats in a raised or lowered position,
wherein one end of said actuator cord is displaced in one longitudinal direction following displacement of the other actuator cord end in the opposite longitudinal direction, causing said driving assembly and each of said tilting devices to rotate in the same rotational direction,
wherein an outer cord is partially wound around, and tensioned by, a corresponding tilting device during rotation thereof, said outer cord being subsequently longitudinally and laterally displaced, causing uniform tilting of each of said slats.
The present invention is also directed to a method for darkening a room, comprising:
a) Providing a manually operated Venetian blind, comprising:
i. providing at least one frame component comprising at least a headrail, and optionally a cover for each of said frame components;
ii. a plurality of transversally oriented, equally sized slats suspended from said headrail by means of at least two ladder braids, wherein each ladder braid comprises two longitudinally extending outer cords, each of which being disposed laterally outward from a different lateral edge of the slats, and a plurality of laterally extending cross ladders, each cross ladder being connected to the two outer cords and supporting a corresponding slat, wherein two outwardly positioned ladder braids optionally further comprise a longitudinally extending central cord passing through each slat;
iii. one or more devices for tilting said plurality of slats, two outer cords of each ladder braid being affixed to a corresponding tilting device, each of said tilting device positioned within one of said frame components and comprising a core member comprising a convex periphery, a toothed key protruding from said periphery, two separated coplanar elements defining a rectangular face which truncate said periphery, two transversally extending grooves obliquely oriented with respect to said coplanar elements, a portion for tensing an outer cord formed between one of said grooves and the corresponding planar element, and a circumferential, rectangularly shaped recess formed between said toothed key and a corresponding laterally oriented wall of said core member; and two oppositely oriented wing members which are engageable with said core member, each of said wing members being provided with a convex shell having a curvature substantially equal to that of the periphery of said core member and being positioned such that the axis thereof is transversally extending, a first transversal end of said shell formed with two openings so as to define a central shell portion and two peripheral portions and with a lip circumferentially extending along the inner wall of said shell, each of said peripheral portions being considerably thicker than said central portion and being configured to be received within a corresponding groove of said core member, a second transversal end proximate to said toothed key having a laterally oriented circumferential wall extending between said two peripheral portions along the inner wall of said shell, and a plurality of radially extending teeth formed in said laterally oriented circumferential wall, each of said teeth being configured with a sufficient length and spacing therebetween so as to abut complementary recessed sharp edge junctions of said toothed key, wherein said teeth of each wing member retain a corresponding outer cord of a ladder braid of the blind which is placed on the periphery of said core member in pressed relation with said toothed key and the lip of each of said wing member is adapted to engage a corresponding recess of said core member with a snapping action to prevent detachment of said corresponding outer cord from the tilting device; and
iv. an actuator for causing rotation of each of said tilting devices;
a) Displacing said actuator a first distance, thereby causing each tilting device to rotate to a first angular distance;
b) Allowing a first outer cord to be partially wound around, and tensioned by, the tensing portion of a corresponding tilting device during rotation thereof to said first angular distance, while a second outer cord is slackened;
c) Allowing said first outer cord to be longitudinally and laterally displaced by the pressing of the tensing portion of a corresponding side of said corresponding tilting device onto said first outer cord during rotation of said corresponding tilting device, causing uniform tilting of each of said slats;
d) Displacing said actuator a second distance, causing each tilting device to rotate to a second angular distance, the inclination of the slats to further increase to a maximum value and the spacing between said first and second outer cords to be a minimum value, significantly less the spacing between said first and second outer cords when the slats are at a completely open position; and
e) Releasing said actuator when said maximum value of the slat inclination results in the darkening of a room to a desired degree, wherein said actuator is displaced said first and second distances by a continuous hand motion.
The first outer cord presses the plurality of slats and thereby assists in further increasing the inclination of the slats. Due to the increased inclination of the slats, the spacing between the first and second outer cords changes from 17 mm when the slats are in a completely open position to 3 mm when the slats are in a completely closed position.
By the method of the invention, the slats may block up to 93% of the incoming light, and up to 95% of the incoming light when a lower support member of the frame has two longitudinally oriented mounting surfaces.
The present invention is also directed to a method for assembling a Venetian blind, comprising:
a) providing at least one frame component comprising at least a headrail and optionally a cover for each of said frame components;
b) providing a plurality of tilting devices comprising two laterally oriented sides, a rectangular face perpendicular to said laterally oriented sides, and an annular protrusion transversally extending outwardly from each laterally oriented side, wherein each of said tilting devices is rotatable about a transversal axis coincident with the axis of said annular protrusions, the number of employed tilting devices depending on the transversal dimension of said headrail;
c) providing a plurality of ladder braids, wherein each ladder braid comprises two longitudinally extending outer cords and a plurality of laterally extending cross ladders, each of said outer cords being disposed laterally outwardly from a different lateral edge of a plurality of transversally extending slats and each cross ladder being connected to the two outer cords and adapted to support a corresponding slat;
d) forming apertures in an inner transversally extending planar surface of said at least one frame component;
e) securing a plurality of cord guide assemblies to a frame component while placing each corresponding cord guide of said plurality of cord guide assemblies in each of said apertures such that a cord guide is substantially coplanar with the corresponding planar surface;
f) mounting the two annular protrusions of each of said tilting devices on corresponding arcuate walls of each of said cord guide assemblies such that each of said protrusions is rotatable within a corresponding arcuate wall;
g) interconnecting adjacent tilting devices by means of a D-shaped shaft insertable within a corresponding annular protrusion;
h) introducing the two outer cords of a ladder braid through a corresponding outer section of the cord guide such that each outer cord is essentially longitudinally disposed;
i) affixing the two outer cords of a ladder braid to a corresponding tilting device;
j) inserting a drive means adapted to tilt the plurality of slats in one of said frame components and connecting one of said tilting devices by means of a D-shaped shaft to said drive means;
k) connecting an actuator to said drive means; and
l) optionally, interlocking a cover with each corresponding frame component by a snapping motion.
In one aspect, the step of securing a cord guide assembly to a frame component comprises the steps of:
a) providing a substantially rectilinear cord guide assembly having a transversally oriented and inwardly positioned face from which the cord guide longitudinally protrudes, two longitudinally oriented sides, two laterally oriented sides, and four legs, each of said legs abutting a corresponding corner of said cord guide assembly and the longitudinally outward end of each of said legs terminating with a wedge-shaped portion, wherein each of said laterally oriented sides is formed with an arcuate opening on which an annular protrusion of a tilting device is to be mounted and with a substantially rectangular opening which is formed laterally outwardly from the corresponding arcuate opening, thereby affording the corresponding laterally oriented side with increased flexibility;
b) providing a frame component having at least one planar transversally oriented support surface, two longitudinally oriented and transversally extending walls perpendicular to said support surface, and mutually parallel, laterally oriented and transversally extending legs which perpendicularly protrude from the inner side of each of said transversally extending walls such that a first leg has a longer lateral dimension than a second leg, said first leg terminating with a longitudinally oriented abutment surface;
c) flexing a laterally oriented side of said cord guide assembly by bringing two opposed legs corresponding to said laterally oriented side towards each other;
d) inserting each of said wedge-shaped portions of said two opposed cord assembly legs between a corresponding longitudinally oriented abutment surface and wall of said frame component, so as to be compressed and snapped in secured, undetachable relationship with respect to a corresponding set of first leg, wall and abutment surface of said frame component; and
e) repeating steps c) and d) for the other laterally oriented side of said cord guide assembly.
The method for assembling an internal Venetian blind further comprises the steps of:
a) providing two glass sheets of specified dimensions;
b) providing frame components of specified dimensions, said frame components consisting of a headrail, lower support member, and two side members, and a cover for each of said frame components;
c) positioning a first internal magnet housing formed within an outwardly facing cavity in which an internal magnet is placed and two spaced coplanar abutment plates such that one of said abutment plates is in communication with the drive means;
d) interlocking a cover with each corresponding frame component by a snapping motion;
e) connecting each of side members to said headrail and said lower support member to produce a blind frame;
f) bonding said two glass sheets to the front and rear of said blind frame;
g) inserting said blind frame in a suitably sized frame of a wall opening;
h) mounting a first actuator guide by a press fit between a glass sheet and a frame element of said wall opening in such a way so as to correspond to an intended displacement path of said internal magnet; and
i) mating a first external magnet housing containing at least one external magnet with said first actuator guide such that said at least one external magnet is in opposed relation to, and at a fixed distance from, said internal magnet of said first internal magnet housing and that said first external magnet housing is slidingly displaceable within said first actuator guide, whereby said plurality of slats are uniformly tiltable upon linear displacement of said first external magnet housing.
In one aspect, the method further comprises the steps of:
a) additionally providing two outwardly positioned ladder braids with a longitudinally extending central cord passing through each slat;
b) introducing each central cord of a ladder braid through a corresponding inner section of the cord guide such that each central cord is essentially longitudinally disposed;
c) affixing a stabilizer proximate to the upper longitudinal end of a first side member;
d) securing a bearing housing which houses a ball bearing to the upper longitudinal end of said first side member;
e) interconnecting a bifurcated bearing block which houses a ball bearing with a counterweight which houses at least one inner magnet in an outward portion thereof;
f) introducing said bearing block and said counterweight within said first side member such that said bearing block and said counterweight are longitudinally displaceable within said first side member;
g) transversally orienting the two central cords through the headrail;
h) winding the two central cords around the ball bearing housed in said bearing housing;
i) winding the two central cords around the ball bearing housed in said bearing block and then affixing the ends of each central cord to said stabilizer;
j) mounting a second actuator guide by a press fit between said glass sheet and said frame element of said wall opening in such a way so as to correspond to an intended displacement path of said at least one internal magnet housed within said counterweight; and
k) mating a second external magnet housing containing at least one external magnet with said second actuator guide such that said at least one external magnet is in opposed relation to, and at a fixed distance from, said at least one internal magnet of said counterweight and that said second external magnet housing is slidingly displaceable within said second actuator guide, whereby said bearing block and said counterweight are longitudinally displaceable upon linear displacement of said second external magnet housing.
In the drawings:
The present invention is a novel manually operated internal Venetian blind with a surface area of up to 5 square meters that can be lowered/raised and tilted effortlessly and speedily, whose operating mechanism can be adjusted to the dimensions of the blind, and which can be inverted without disarray of the slats and of the cords.
The first embodiment of the present invention relates to an internal Venetian blind for tilting a plurality of slats. Several prior art internal Venetian blinds comprise a tilting mechanism in the headrail in which outer cords of a ladder braid are wound around a cylindrical element, which is generally driven by gears, or any other type of transmission in communication with an actuator external to the Venetian blind. Since this cylindrical element is housed within the headrail, the circumference of the cylindrical element is laterally spaced from the lateral periphery of the slats across which the outer cords extend. Spacers placed on the transversal periphery of the uppermost slat are therefore needed to direct the outer cords to the cylindrical element. Such an arrangement for the tilting of Venetian blinds suffers from several drawbacks. Firstly, the weight of the slats is concentrated disproportionally more on the spacers and on the uppermost slat than on the other slats, causing the slats to change their relative position, or even to fail, over the course of time. Secondly, each outer cord is affixed to the cylindrical element by means of a clasp whose two legs are pressed onto the outer cord. Over the course of time, an outer cord may be released from its clasp, due to the weight concentration on a spacer or a change in the relative positions of the slats. Also, due to the angle of the outer cords resulting from the addition of the spacers, the slats cannot completely close and invariably only 75% of the incoming light is blocked.
In contrast, the tilting device of the present invention is rectangular, and the outer cords retain an essentially vertical disposition from the headrail to the lower rail. The outer cords are not affixed to the outer periphery of the tilting device, but rather to apertures formed within a planar surface of the tilting device, as will be described hereinafter. The weight of the slats is therefore more evenly distributed than in the prior art, allowing the slats of a blind unit with a higher surface area than has been known heretofore to be tilted, with greater reliability and without use of a gear train or any other transmission.
Referring now to the drawings,
As further shown in
The structure of lower rail 52, which is arranged in mirror symmetry with respect to headrail 2, is illustrated in
With reference to
When slats 14 are of an increased transversal length, e.g. 1.5 m due to a corresponding increased surface area of the blind, more than two ladder braids are employed. The two outer ladder braids are composed of three cords as described hereinabove wherein central cord 45 thereof is passed through similarly located aperture 55 formed within the slat. The remaining ladder braids are composed of outer cords 46 and 47 and a plurality of cross ladders 48 for supporting each corresponding slat 14, without need of a central cord. Accordingly, the inner portions of each slat 14 are formed without an aperture 55.
Each cord guide assembly 36 is substantially rectilinear, wherein face 75 is perpendicular to transversal sides 68 and to lateral sides 64. Trapezoidal opening 63, or an opening of any other convenient shape, is formed in each transversal side 68, such that a portion is removed from the transversal edge of face 75. Rectangular cord guide 61 is centrally located within, and protrudes from, face 75. Cord guide 61 is divided into three sections by dividers 62A and 62B so that each cord passes through a different section and is essentially vertically disposed. The cord guide 61 of each cord guide assembly 36 is internally positioned, i.e. it faces the cavity of internal blind 10, and is substantially coplanar with the inner planar surface 65 of either headrail 2 or of lower rail 52, protruding from a similarly shaped aperture formed in said outer planar surface so as to be accessible to the cords 45-47.
Cord guide assembly 36 is adapted for rotatably supporting tilting device 31 (
Cord guide assemblies 36 are immobilized within lower rail 52 (
As shown in
Referring now to
As shown in
Therefore the weight of slats 14 is substantially evenly distributed throughout the length of the outer cords, resulting in added reliability without danger of slat failure. Also, the circular apertures 81 and 82 (
When the slats are in a completely open position as illustrated in
As previously mentioned, the tilting of the slats is accomplished by rotating tilting device 31 about axis C-C (
The drive means for this embodiment is illustrated in
Helical member 33 is placed between two coplanar, laterally oriented abutment plates 92 of internal magnet housing 23. Following transversal displacement of actuator 40, and consequently of abutment plates 92 as well, one of the abutment plates contacts a twist 94 of helical member 33. The twist in contact with an abutment plate is in turn transversally displaced in a similar direction, and then that twist follows a helical path, due to the shape of member 33. Helical member 33 therefore is therefore rotationally displaceable since all portions thereof follow a helical path. It will be appreciated that the rotational displacement of helical member 33 per stroke of actuator 40 is dependent on the pitch, or numbers of twists for a given length, of the helical member. Therefore a shorter helical member 33 can be rotationally displaced as much as a longer helical member if the shorter member is provided with a greater pitch.
Two sets of tilting devices are provided, wherein one set is positioned in headrail 2 and the other in lower rail 52. By utilizing transversally extending D-shaped shaft 29 to connect between adjacent tilting devices, the spacing between a pair of tilting devices 31 is adjustable. A tilting device 31 or adapter 30 may be effortlessly pushed along shaft 29, whereby to define a transversal position of the tilting device within the corresponding rail. Following adjustment of the spacing between adjacent tilting devices, an end 96 of D-shaped shaft 29 may inwardly protrude within the cavity of tilting device 31 or adapter 30. If the transversal length of an internal blind is relatively long, more than two tilting devices, with suitable connections thereto such as an additional helical member or shaft, may be employed. If so desired, the drive means may be positioned in headrail 2, for example if the lower rail is in an inaccessible location. Therefore the drive means may be effortlessly customized to any desired transversal length, e.g. from 2 cm to 8 m, without any compromise in reliability, rate of actuation, comfort or safety.
The slats of the present invention can be tilted effortlessly and speedily from one angular position to another within less than 2 seconds regardless of the surface area of the Venetian blind. Such quick tilting is realized due to the configuration of actuator 40, which is shown in
As shown in
Internal magnet housing 23 is integrally formed with longitudinally oriented stopper 110 and cavity back 116, transversally oriented bridge 112, and laterally oriented abutment plates 92 and legs 114. The longitudinal dimension of stopper 110, which is sidable along wall 122 of lower rail 52 (
The outwardly facing cavity in which internal magnet 89 is placed is defined by legs 114, cavity back 116 and bridge edge 113, and is suitably sized so that the internal magnet contacts wall 123 of lower rail 52 (
The transversal displacement of actuator 40, and therefore the rotation of tilting device 31 as well due to the kinematic relationship described hereinabove between external magnet housing 19 and tilting device 31, is limited by stopper 110, as the stopper abuts leg 57 and straight wall 70 of cord guide assembly 36 (
In contrast with prior art internal blinds with which great care has to be taken so that the slats remain horizontally disposed during shipping, handling and installment in order to avoid transversal cord movement and subsequent entanglement in other cords and/or slats, the present invention employs a central cord tensioning means. By applying a tensile force, e.g. of 0.5 kg, to the central cord, the central cord, as well as the outer cords connected thereto by means of the cross ladders of a ladder braid, will remain essentially perpendicular to planar surface 65 of lower rail 52 (
After suspending the slats from a suitably sized headrail 4, the aluminum frame of blind 130 is assembled in the manner illustrated in
It will be appreciated that cover 5 need not be interlocked with any of the aforementioned components by being inserted at an end of the component, e.g. a longitudinal end of side member 3. Cover 5 is advantageously adapted to be interlocked with a corresponding component by a single snap, e.g. at the lateral centerline of the cover when interlocked with a side member after one leg 125 has been inserted between legs 90 and 91 of a corresponding side member.
Longitudinally extending side member 3, as illustrated in
A transversally extending cover 5 is then connected to headrail 4 and lower rail 52. As illustrated in
After being secured to the longitudinally extending covers, corners 25 are then secured to the transversally extending covers. As shown in
By assembling the blind frame in the manner described hereinabove, each transversally extending cover 5 abuts two side members 3 and rail 4 or 52, as illustrated in
In this embodiment, one set of tilting device is employed, and is positioned within headrail 4, as illustrated in
Driving assembly 139 is both a means to drive the tilting device and to receive D-shaped shaft 29, and is adapted to convert longitudinal linear motion of the actuator into rotational motion. Driving assembly 139 is produced by the steps illustrated in
Since the tilting devices are directly driven by the driving assembly, a greater rotational displacement by the tilting device may be realized.
The maximum rotational displacement of the tilting device shown in
An alternative embodiment of a driving assembly, which is adapted to rotate a tilting device to such an extent so as to block up to 90% of the incoming solar radiation, is illustrated in
In order to affix actuator cord to casing 215, knot 224 is tied at the middle of actuator cord 142. The ends of actuator cord 142 are then introduced into the outward end of casing 215, through the interior thereof, and fed through aperture 222 bored in the periphery of casing 215. After the ends of actuator cord 142 are pulled, actuator cord 142 divides into two portions which dangle over outer wall of casing 215 and extend longitudinally inwardly, and knot 224 engages the inner wall of casing 215. Consequently, actuator cord 142 will not be released from casing 215 as the actuator is longitudinally displaced and driving assembly 210 is thereby rotated.
The raising/lowering arrangement includes bearing housing 8, bifurcated rectangular bearing block 20 and lead counterweight 1, all positioned within the interior of side member 3. Ball bearing 35 having opposed axles 38 (
In addition to ball bearing 35, a pair of plain bearings (not shown) is housed in housing 8. Each plain bearing encircles, supports and centers a corresponding axle 38 of the ball bearing. Each plain bearing presses against a corresponding transversal wall 132 (
When sections 153A and 153B are mated, as shown in
Referring now to
Internal magnets 89 are housed in the outward portion 169 closest to the external magnet housed in external magnet housing 19 (
Bearing block 20 (
Alternatively, the counterweight may be embodied by a plurality of rectangular metallic plates, e.g. steel, as shown in
While each longitudinal edge 181 of elongated plates 182 is longitudinally aligned with the corresponding longitudinal edge 183 of the frontmost shortened plate 184, longitudinal edge 188 of the other shortened plate protrudes from longitudinal edge 181 of elongated plates 182 to such a degree that hole 187 remains uncovered by the frontmost shortened plate. Consequently, the upper hole 187 of the second shortened plate 184 is available for affixing thereto the means for interconnecting counterweight 180 and bearing block 20 (
Blind 290 is sized to substantially correspond to the dimensions of the wall opening. Blind 290 is inserted in the wall opening when securing elements 558 are removed from frame 550. Silicone sealant 69 (
Body 320 shown in
Each dirt removing channel 327 is defined by a transversally oriented plate 328 extending from approximately the middle of a corresponding compartment wall 325, a laterally oriented channel wall 329 extending inwardly from plate 328, and wall 325, wherein the inward edge of a wall 325 and the corresponding leg 329 are coplanar. Two opposed wiper elements 324A and 324B, which are essentially coplanar with back 322, extend transversally from channel wall 329 and compartment wall 325, respectively, towards the interior of the corresponding dirt removing channel 327. As external magnet unit 310 is displaced, wiper elements 324A and 324B contacting the front glass sheet of the blind scrape any dirt that has accumulated on the glass sheet. A brush (not shown), e.g. having bristles made from Teflon, is adapted to remove the collected dirt from channel 327. The brush handle may be structured to be insertable in the groove between wiper elements 324A and 324B and plate 328, for storage when not in use.
Magnet cover 330 shown in
After body 320 is coupled to track 102 of actuator guide 6, magnets 315 are inserted into the magnet retaining compartment as shown in
As previously mentioned, the internal blind of the present invention may be inverted without loss of operability when reoriented to a working position. In this embodiment, reliable operation of the blind is ensured by retaining the central cords at substantially the lateral centerline of headrail 4, as shown in
A means for centering central cord 45 illustrated in
As shown in perspective view in
Partitions 178 of cord guide assembly 37A advantageously urge the central cord associated with ladder braid 13A to remain in the center of rectangular opening 173. When the internal blind is tilted to an angle of 45 degrees, for example, relative to the ground, central cord 45 contacts one of the partitions 178, and therefore additional lateral movement is prevented. When the blind is completely inverted, each central cord contacts the wall at the longitudinal end of the corresponding rectangular opening 173. After the blind is reoriented to its original position the central cords contact again the ball bearing of each cord guide assembly 37, as described hereinabove, and are thereby centered within the headrail. The lateral centering of the central cords is additionally facilitated by the ball bearing 35 of bearing housing 8, which is centrally positioned within side member 3 by means of plain bearings, as described hereinabove, and by ball bearing 35 of bearing block 20, which is centered by its two sections 153A and 153B (
After annular protrusions 85 of tilting device 31 (
The blind may be advantageously raised and lowered even when the blind is at an inclination of up to 45 degrees relative to the ground, such as within a skylight. As shown in
With reference to
The transversal dimension of periphery 430 is longer than the combined length of the two wing members 460A and 460B. Coaxial protrusions 416 and 417 extend transversally from each laterally oriented wall 415, wherein protrusion 416 has a greater outer diameter than protrusion 417 and laterally oriented face 418 of protrusion 417 is formed with a D-shaped aperture 419. The two D-shaped apertures 419 of core member 420 are aligned and are adapted to receive a D-shaped shaft, which may extend internally within channel 448 formed between elements 442. Elements 442 face outwardly when the slats of the blind are in a completely open position.
The entire length of convex periphery 430 including walls 415 is formed with two transversally extending grooves 404, each of which being formed at a different lateral side of protrusions 416. Each groove 404 has a rectangular cross section which is obliquely oriented with respect to coplanar elements 442. The two grooves 404 are separated by an angular distance of approximately 120 degrees and have bilateral symmetry. Portion 425 of convex periphery 430 between a groove 404 and the corresponding rectangular element 442 serves to tension an outer cord, as will be described hereinafter.
Convex periphery 430 is also formed with two circumferential, rectangularly shaped recesses 438 proximate to the transversal ends, respectively, of periphery 430. Recesses 438 and toothed key 435 have a substantially equal circumferential length and are equally spaced between grooves 404. Toothed key 435 is formed at the transversal centerline of periphery 430 and is integral therewith. Toothed key 435 has a series of laterally separated toothed serrations 458 of equal length and of similar configuration with alternating protruding pointed ends and recessed sharp edge junctions, on each transversal end thereof.
Wing members 460A and 460B are illustrated in
Transversal end 478 also has a laterally oriented circumferential wall 481, which extends between the two peripheral portions 473 along the inner wall of periphery 465. A plurality of radially extending teeth 485 are formed in a central region of circumferential wall 481. Teeth 485 are configured with a sufficient length and spacing therebetween so as to abut the recessed sharp edge junctions of toothed serrations 458 of toothed key 435. Transversal end 479 of wing member periphery 465 has a lip 492 which circumferentially extends along the inner wall of shell 465. Lip 492 has a circumferential length substantially equal to recess 438 of core member 420, and is adapted to engage the same with a snapping action.
In order to affix outer cords 46 and 47 to tilting device 400, outer cords 46 and 47 are first placed on periphery 430 of core member 420 in contact with the two transversal ends of serrations 458, respectively, while in a lateral orientation and dangling from a corresponding tensing portion 425 of core member 420, as shown in
It will be appreciated that tilting device 400 is suitable for tilting the slats associated with a blind of any of the aforementioned embodiments, for example the blind illustrated in
With reference to
1) A blind frame from PVC significantly reduces the cost of the blind. Since painted aluminum costs approximately $4/kg and PVC costs approximately $1.40/kg and the density of PVC is approximately one-half of aluminum, the cost of a blind frame made from PVC is approximately one-sixth of one made from aluminum.
2) The thermal conductivity of PVC is significantly less than that of aluminum (237 W/mK for aluminum and only 0.16 W/mK for PVC at 20° C.), and therefore a blind frame from PVC serves as thermal insulation, being well suited to very hot or very cold climates.
3) PVC is produced by extrusion. During the extrusion process, a PVC component may be produced with two layers wherein the base layer has a thickness ranging from 1-2 mm and the outer layer has a thickness ranging from 0.2-0.3 mm. The outer layer may be dyed to any desired color, and therefore the blind frame may be custom made. In contrast, aluminum needs to be painted separately after being produced, further increasing its price.
As shown in
A side view of headrail 254 is illustrated in
A perspective view of transversal cover 255A is illustrated in
A side view of a transversal cover 255A being interlocked with headrail 254 is illustrated in
Support member 259, as illustrated in
During the extrusion of support member 259, plate 283 thereof is formed with a plurality of apertures 291. Consequently, the holding chamber defined by the volume between plate 283 of support member 259 and transversally oriented base portion 273 of transversal cover 255A, when support member 259 and transversal cover 255A are coupled, communicates with the interior of the blind via apertures 291. Hydrophilic pellets 293 placed within the holding chamber absorb any moisture that infiltrates to the interior of the blind.
Side element 253 is illustrated in
As shown in
In
Transversal cover 255A is positioned such that side walls 272 are transversally extending and longitudinally oriented, and base portion 273 is transversally extending and oriented. Apertures 298 bored within base portion 273 and surface 279 (
Alternatively, as shown in
When slats 14 are completely lowered, as shown in
Blind 500 advantageously provides tilting and raising/lowering arrangements that are directly driven, without need of a gear train or any other transmission, as has been employed heretofore in prior art external blinds, thereby lowering the cost of the blind. Additionally, tilting devices 31 and/or 400, about which the outer cords are wound upon rotation of driving assembly 210, are configured to simplify the mounting thereof on cord guide assembly 37 and the affixation of the outer cords thereto, and to furthermore allow the outer cords to be essentially longitudinally disposed from headrail 254 to slat support 7, thereby affording the blind with increased reliability with respect to the prior art. Also, tilting devices 31 and/or 400 can rotate an increased angular distance with respect to those of the prior art, and therefore blind 500 can block at least 90% of the incoming light. Moreover, cord guide assembly 37 provides a lateral centering capability of the central cords, so as to prevent entanglement of the cords during transportation of the blind.
It will be appreciated that any other aforementioned configuration of the cord guide assembly, driving assembly, headrail, and transversal cover may similarly be employed in conjunction with blind 500.
A manually operable internal Venetian blind adapted for tilting and lowering/raising a plurality of slats was tested for reliability by Hollis Metal Industries Ltd., Industrial Zone Alon-Tavor, Israel between May 29, 2005 and Jun. 21, 2005. The Quality Assurance Group supervised the measurement of the tolerance tests, and the Electronic Group supervised the counting of the testing cycles and verified the operation of the testing apparatus.
The blind had a height of 200 cm and a width of 100 cm, and the slats had a width of 16 mm. The lowering/raising arrangement had a stroke length of 80 cm, i.e. 40% of the distance to which the longitudinally lowest slat is raised or lowered. The tilting arrangement had a stroke length of 4 cm. The arrangement for tilting the slats included a driving assembly having a D-shaped core and a plurality of radially extending ribs, and tilting devices to which the corresponding outer cords were affixed by nails having radial protrusions. A laterally centering cord guide assembly was used.
The blind was mounted without its glass sheets onto a custom made testing apparatus. The testing apparatus had a motor for actuating the tilting arrangement and the lowering/raising arrangement simultaneously, an electronic control system for the motor, sensors for detecting the end of the actuator stroke, and an electronic counting system. A first pulley and a second pulley having a considerably smaller diameter than that of the first pulley were mounted on the drive shaft of the motor, and a third pulley was driven by a cord wound around the second pulley. A cord wound around the first pulley was connected to the counterweight of the lowering/raising arrangement and simulated the action of a linear actuator. The cord wound around the third pulley was connected to the internal magnet housing of the tilting arrangement, to which was connected another counterweight, and simulated the action of a linear actuator. The transmission of the first, second and third pulleys was such that the stroke length ratio of the tilting arrangement counterweight to the lowering/raising counterweight was 1:20, and the tilting and lowering/raising arrangements underwent the same number of testing cycles. The bearing housing was removed from the tilting arrangement since glass sheets were not used. The testing conditions did not simulate solar radiation radiating on the blind.
Prior to the first testing cycle, selected components of the blind were visually inspected and measured. Each measurement had a tolerance of 0.001 mm. The following components were selected for inspection and measurement:
a) bearing housing;
b) driving assembly;
c) cord guide assemblies;
d) 3 tilting devices;
e) nails with radial protrusions;
f) 2 bearing blocks;
g) interconnecting plastic rod;
h) 2 plain bearings: housed in a bearing block;
i) 4 bearings made from polyacetal: housed in a bearing housing of the tilting arrangement and in a cord guide assembly; and
j) 2 ball bearings: housed in a bearing block and bearing housing.
After inspection, the components were assembled and a first group of 26,680 testing cycles was performed. Each testing cycle included the following steps applied to the lowering/raising arrangement: a) the counterweight was raised for a duration of 13 seconds; b) a delay of 3 seconds; c) the counterweight was lowered for a duration of 10 second; and d) a delay of 2 seconds. The aforementioned components were removed from the blind, and a second visual inspection and measurement of the components was performed. The measured level of wear of the aforementioned components did not exceed the permissible value of 1 mm, with greatest measured level of wear being no more than 0.4 mm.
The aforementioned components were assembled and a second group of 20,180 testing cycles was performed. The aforementioned components were removed from the blind, and a third visual inspection and measurement of the components was performed. The measured level of wear of the aforementioned components ranged from 0-0.7 mm. Some small signs of wear were noticeable on the metallic components which did not negatively influence the operation of the blind. With the exception of the interconnecting plastic rod, no signs of wear were noticeable on the plastic components. Some small signs of wear were noticeable on the interconnecting plastic rod which did not negatively influence the operation of the blind.
The following are three examples of the measured wear:
A) Diameter of the arcuate opening of the cord guide assembly—
B) Diameter of the inner portion of the ball bearing housed in the bearing block, over which the central cords were wound—
C) Diameter of the connecting element which transversally extends between the longitudinally rod and the contractible elements of the interconnecting plastic rod—
The diameter of the connecting element remained greater than the accepted tolerance of 2 mm.
Since the blind is actuated on the average 3 times a day, it can be concluded, after a total number of 46,860 testing cycles without noticeable wear, that the blind of the present invention can operate reliably for at least 42 years without failing.
While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried into practice with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without, departing from the spirit of the invention or exceeding the scope of the claims.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IL05/00747 | 7/14/2005 | WO | 00 | 3/11/2008 |
