United States Patent
`
`[19]
`
`[11] Patent Number:
`
`5,531,257
`
`
`Kuhar
`[45] Date of Patent:
`Jul. 2, 1996
`
`lllllllllllllllllllllllllll|||||lllllllllllllllllllllllllllllllllllllllllll
`USOOSS31257A
`
`{54] CORDLESS, BALANCED WINDOW
`COVERjNG
`
`2,390,826 12/1945 Cohn.
`2,420,301
`5/1947 Cusumano.
`2,824,608
`2/1958 Etten.
`
`{75]
`
`Inventor: 0m, Kuhar, Gal-field, NJ.
`-
`.
`«
`{73] Assrgnee.
`fillewell Operating Company, Freeport,
`'
`
`[21] Appl. N0.: 303,773
`,
`[221 Filed:
`
`5811-9: 1994
`
`Related US. Application Data
`
`[63] Continuation—impart of Ser. No. 223,989, Apr. 6, 1994, Pat.
`No. 5,482,100.
`
`Int. 01.6 ........................................................ F06B 9/30
`[51]
`[52] US. Cl. ............... 160/168.1; 160/170; 160/DIG. 17
`[58] Field of Search ........................ 160/ 168.1 R, 170 R,
`160/171 R, 172 R, 84.02, 84.04, 84.06,
`191, 193, 192, 168.1 P; 267/155, 156; 185/37,
`39, 45
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`7/1855 Bixler .
`13,251
`7/1929 McKee .
`1,721,501
`2,266,160 12/1941 Burns .
`2,276,716
`3/1942 Cardona .
`2,324,536
`7/1943 Pratt .
`
`
`3,194,343
`7/1965 Sindlinger ............................. 185/39 X
`3,358,612 12/1967 Bleuer ..........
`....267/156X
`................... 160/168.1P
`4,856,574
`8/1989 Minami et a1.
`5,054,162 10,1991 Rogers.
`5,133,399
`7/1992 Hilleret a1.
`.................... 160/170RX
`5,157,808 10/1992 Sterner .....
`267/156X
`
`5,170,830 12/1992 Coslett .......... 160/84.04
`
`5,363,898 11/1994 Sprague ............... 160/191X
`
`5,391,967
`2/1995 Domeletal.
`160/168.1 PX
`..................... 160/168.1Px
`5,413,161
`5/1995 Corazzini
`
`Primary Examiner—David M. Purol
`Attorney, Agent, or Firm—Foley & Lardner
`
`ABSTRACT
`7
`[57]
`A cordless, balanced venetian blind or shade with a constant,
`or a variable force spring motor includes conventional
`window covering components without the outside hanging
`lifting cords or cord locking mechanisms. One or more
`spring motors are employed. A cord spool, in the preferred
`embodiment, is coupled to one of the spring drums to serve
`to wind the cords to cause the blind to be raised or lowered,
`simply by manipulation of the bottom bar of the blind
`system. Due to the spring forces, the system compensates for
`the increasing weight on the cords as the window covering
`is raised and for the decreasing weight as it is lowered.
`
`20 Claims, 3 Drawing Sheets
`
`£174
`
`
`
`Norman Int. Exhibit 1004 Page 1
`
`Norman Int. Exhibit 1004 Page 1
`
`

`

`US. Patent
`
`Jul. 2, 1996
`
`5
`
`Sheet 1 of 3
`
`5,531,257
`
`
`
`Norman Int. Exhibit 1004 Page 2
`
`Norman Int. Exhibit 1004 Page 2
`
`

`

`US. Patent
`
`Jul. 2, 1996
`
`Sheet 2 of 3
`
`5,531,257
`
`
`
`Norman Int. Exhibit 1004 Page 3
`
`Norman Int. Exhibit 1004 Page 3
`
`

`

`US. Patent
`
`Jul. 2, 1996
`
`Sheet 3 of 3
`
`5,531,257
`
`”a
`
`”4
`
`//é
`
`£34
`
`Norman Int. Exhibit 1004 Page 4
`
`Norman Int. Exhibit 1004 Page 4
`
`

`

`1
`
`CORDLESS, BALANCED WINDOW
`COVERING
`
`CROSS—REFERENCES TO RELATED
`APPLICATIONS
`
`The present invention is a continuation-in-part of U.S.
`patent application Ser. No. 08/223,989, filed Apr. 6, 1994,
`now U.S. Pat. No. 5,482,100, issued Jan. 9, 1996.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`
`The present invention relates generally to the art of spring
`motors useful for a variety of applications, including vene-
`tian blinds and window shades. More specifically the present
`invention relates to a system in which lifting cords and cord
`locking mechanisms are eliminated from shades or blinds.
`Still more specifically,
`the invention relates to window
`covering systems which employ one or more constant or
`consistent, variable force springs to balance the weight of
`accumulated window covering material, depending upon the
`extent to which the blind or shade is raised or lowered. The
`present
`invention also relates to motorized blinds and
`shades.
`
`2. Description of the Prior Art
`Venetian blinds have been kn0wn for many years and
`typically include a plurality of slats made from metal,
`plastic, wood or other materials and supported by ladders.
`Such blinds typically include a bottom bar and a tilt mecha-
`nism to cause the slats to move from a horizontal position to
`a nearly vertical position to open and close the blinds with
`respect to the passage of light. It is also conventional with
`such systems to use lifting cords coupled to the bottom bar,
`passing through the slats and into mechanisms within the
`blind headrail. The cord is used to raise the bottom bar,
`accumulating individual slats as the bar is raised. Because of
`the natural tendency of the bar and accumulated slat weight
`to free fall,
`locking mechanisms are also commonly
`employed with such prior art devices. Pleated and other
`types of shades also include a bottom bar and similar raising,
`lowering, and cord locking mechanisms.
`Several attempts have been made to eliminate the lifting
`cord locks, some of such attempts going back nearly 140
`years. See, for example, Bixler, U.S. Pat. No. 13,251, issued
`Jul. 17, 1855 for “Inside Blinds.” In this device, a pair of
`“fusees” are employed, namely spirally grooved pulleys, to
`wind a cord passing therebetween. The two fusees are
`arranged so that as a barrel spring is being wound the cord
`joining the fusees compensates for changes in spring force.
`A spool is provided for accumulation of the lifting cord.
`U.S. Pat. No. 2,420,301,
`issued May 13, 1947 to
`Cusumano for “Venetian Blind” also employs a cone—shaped
`member with grooves and an elongate coil spring. This
`design dispenses with normal draw cords and provides a
`counterbalance so that the slats may be retained at any
`vertical position without a lock or anchorage and so that the
`blinds can be raised with relatively small efiort.
`A different device is shown in Pratt’s U.S. Pat. No.
`2,324,536 issued Jul. 20, 1943 for “Closure Structure.” In
`this device, tapes and coil springs are employed to raise and
`lower a blind particularly suited for use in a vehicle such as
`a train. The complex structure disclosed in this patent is
`especially suitable for devices in which the bottom bar and
`the slats ride in tracks as they move upwardly and down-
`wardly.
`
`10
`
`15
`
`20
`
`25
`
`3O
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`
`4o
`
`45
`
`SO
`
`55
`
`60
`
`65
`
`5,531,257
`
`2
`
`Other patents show various spring devices used with
`venetian blinds. For example,
`in Cohn’s U.S. Pat. No.
`2,390,826,
`issued Dec. 11, 1945 for “Cordless Venetian
`Blinds,” two coil springs are used to provide even force,
`with a centrifugal pawl stop. The blind is raised by freeing
`the pawl to allow the spring to provide a lift assist. Other
`more conventional systems employing springs and ratchet
`and pawl mechanisms include those shown in Etten’s U.S.
`Pat. No. 2,824,608,
`issued Feb. 25, 1958 for “Venetian
`Blind”; U.S. Pat. No. 2,266,160, issued Dec. 16, 1941 to
`Burns for “Spring Actuated Blind”; and U.S. Pat. No.
`2,276,716, issued Mar. 17, 1942 to Cardona for “Venetian
`Blind.”
`
`Various attempts have also been made in the prior art to
`motorize blinds and shades. In most of these systems hard
`wiring is required because larger motors are required to
`move the bottom rail and accumulated window material.
`
`None of the aforementioned patents disclose the use of
`spring motors of the type disclosed herein to eliminate the
`conventional pull cords and locks of venetian blinds or
`shades in a simple and easily adaptable mechanism having
`few components parts. A system which overcomes the
`disadvantages of the more complex and cumbersome sys-
`tems of the prior art would represent a significant advance in
`this art.
`
`SUMMARY OF THE INVENTION
`
`The present invention features a cordless blind or shade in
`which a spring motor is used to eliminate conventional pull
`cord and cord-lock mechanisms.
`
`The present invention also features a system in which
`either the spring strength or the number of spring motors
`may be altered, depending upon the size of the window
`covering. The invention further features techniques for
`increasing the friction on the cords used to raise and lower
`the blinds or shade to assist in maintaining a desired position
`against any spring force which may exist through the range
`of travel of the bottom bar.
`
`The present invention still further features a system which
`is easy to adapt to a wide variety of blind or shade designs
`and sizes and the capability of applying spring forces in a
`variety of ways and combinations.
`A difierent feature of the present invention is the use of
`spring motors and small electric motors to provide highly
`desirable automatic or remote controlled capabilities for
`shades and blinds.
`
`How the present invention accomplishes these features
`will be described in the following detailed description of the
`most preferred embodiments, taken in conjunction with the
`FIGURES which illustrate blind systems, although shade
`applications are also enhanced by the present invention.
`Generally, however,
`the features are accomplished by .
`employing constant force or consistent variable force spring
`motors in a blind or shade system, while eliminating con-
`ventional pull cord and associated cord-lock mechanisms.
`The features are accomplished by using springs wound on
`drums, the springs being of constant cross-section (constant
`force) or varying in width, thickness, or both along their
`length (variable force) whereby spring force imparted to a
`coiled spring is transferred from one drum to another. For
`these spring motors, such force is at its highest level when
`the blind or shade is fully raised, i.e., when the cords are
`supporting the full weight of the window covering. The
`spring force is at its lowest point when the window covering
`is fully lowered and, in the case of blinds, the slats are being
`
`Norman Int. Exhibit 1004 Page 5
`
`Norman Int. Exhibit 1004 Page 5
`
`

`

`3
`
`4
`
`5,531,257
`
`individually supported by ladders, rather than by the cords,
`leaving only the bottom bar to be supported by the cord. In
`constant force systems,
`the spring force is substantially
`constant throughout the range of movement of its shade or
`blind bottom rack. The blinds and shades of the present
`invention may be manipulated by the operator simply grasp-
`ing the bottom bar and urging it in an upward or downward
`direction.
`
`The features of the present invention are also accom-
`plished by providing selection criteria for the springs, to take
`into account the size and weight of a particular blind or
`shade or by adding additional spring motors for heavier or
`wider window coverings. To achieve greater certainty in
`maintaining desirable spring forces, in a most preferred,
`alternate form of the invention, the spring motors are inter—
`connected to ensure that they operate in unison to provide a
`level action throughout the range of blind or shade travel. All
`of these features are accomplished in a blind or shade which
`will remain in the position selected by the user and which in
`a preferred embodiment may be motorized, e.g. by a small
`remote controlled DC motor. In an illustrated embodiment,
`friction imparting devices are, if necessary, used with the
`cords coupling the bottom bar and a spool within the
`headrail.
`
`Other features of the invention, and other ways in which
`those features are accomplished, will become apparent to
`those skilled in the art after the detailed description of the
`most preferred embodiment is read and understood. Such
`other ways are deemed to fall within the scope of the
`invention.
`
`DESCRIPTION OF THE DRAWINGS
`
`FIG. 1A is a perspective view of a spring storage drum
`useful in one preferred form of the present invention;
`FIG. 1B is a perspective view of output drum, combined
`with a cord spool, useful in this preferred form of the present
`invention;
`
`FIG. 2 is a schematic view of a spring motor together with
`one form of friction imparting device;
`FIG. 3 is a schematic illustration of a combination of three
`
`spring motors, with the cord spools coupled together to
`ensure that all motors operate in unison;
`_
`FIG. 4A is a perspective view of a strip of spring material
`varying in width along its length;
`FIG. 4B is a schematic View of the spring shown in FIG.
`4A wound into a coil;
`
`FIG. 5A is a schematic View of a spring varying in
`thickness along its length;
`FIG. 5B is a View of the spring of FIG. 5A shown in a
`coiled position;
`_
`FIG. 6 is a schematic representation of a blind in the fully
`open position with the cord storage drum fully wound and a
`spring wound on its storage drum,
`the system thereby
`supporting the full weight of the slats and bottom bar;
`FIG. 7 is a schematic illustration of the blind shown in
`FIG. 6, with the bottom bar in its fully lowered position and
`illustrating how the storage drum for the cords is substan-
`tially empty and the spring substantially transferred from its
`storage drum to its associated output drum; and
`FIG. 8A is a perspective view of a strip of spring material
`being generally uniform in cross section along its length,
`FIG. SB is a schematic View of the spring shown in FIG.
`8A wound into a coil; and
`
`10
`
`15
`
`20
`
`25
`
`3O
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`FIG. 9 is a view, similar to FIG. 6, but showing in
`schematic form a motor system for raising and lowering the
`blind.
`
`In the various FIGURES, like reference numerals are used
`to indicate like components.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`Before proceeding with the detailed description of the
`preferred embodiments, several comments should be made
`about the applicability and the scope of the present inven—
`tion. First, while venetian-type blinds are shown in certain of
`the FIGURES, the types of materials from which the blinds
`are made or the relative widths, heights and the configura—
`tion of the headrail, bottom rail and slats may vary widely.
`The present invention has applicability to a variety of such
`blinds. The present invention is also useful with window
`shades of various types since many shade designs also use
`lifting cords and would benefit from the features of this
`invention. Whenever blinds are mentioned herein, shades
`should be considered a suitable alternative.
`
`Second, while preferred types of springs are shown, one,
`varying in width, another varying in thickness and a third
`being of constant cross—section, a combination of the three
`could be employed. Other spring configurations could also
`be used, in addition to those having a rectangular cross-
`section. For example, springs with round or oval cross-
`sections, decreasing along its length (for a variable force
`spring) or a laminated spring could also be employed.
`Third, while one example is given of how to interconnect
`a plurality of spring motors, other techniques can be
`employed. For example, a gear system can be employed
`instead of the illustrated bar. The object of illustrative FIG.
`3 is to show how the spring motors can be made to operate
`in unison for level raising or lowering of the blind or shade,
`even if the lifting forces are applied off center. Ideally,
`however, the user should be instructed to apply the lifting or
`lowering force at, or relatively near, the center of the bottom
`rail to maintain desirable balance and to prevent slack from
`being created in the lifting cords.
`Proceeding now to a description of the FIGURES, FIG. 1
`is a perspective view of one storage drum'10 useful in the
`preferred embodiment. Storage drum 10 includes an axial
`hole 12, a cylindrically-shaped spring storage area 14, and a
`pair of walls 16 and 18 which taper upwardly and outwardly
`from area 14. This particular storage drum is especially
`suitable for a spring which varies in width, as will be
`described later in this specification. Drum 10 will be referred
`to herein as a storage drum, i.e. the drum on which the spring
`is initially coiled. The drum 10 would have parallel walls 16
`and 18 for other embodiments such as for the springs
`illustrated in FIGS. 5A, 5B, 8A, and 8B.
`Proceeding next to FIG. 1B, an output drum is shown
`generally at 20 to include an axial hole 22, a cylindrical body
`24, and a pair of walls 26 and 28. A hole 29 is provided on
`body portion 24, the purpose of which will become apparent
`shortly. Output drum 20 also includes a cord spool 30 having
`a central aperture (not shown) coaxial with hole 22, a body
`portion 32, and a pair of parallel side walls 34 and 36
`defining an area therebetween for storage of the lifting cords.
`Proceeding next to FIG. 2, the arrangement of the devices
`in FIGS. 1A and 13 in a spring motor unit .40 is shown.
`Motor unit 40 includes a bracket having a planar back wall
`42 onto which the storage drum 10 and output drum 20 are
`rotatably mounted in a spaced apart orientation. Axles 43
`
`rNorman Int. Exhibit 1004 Page 6
`
`Norman Int. Exhibit 1004 Page 6
`
`

`

`5,531,257
`
`5
`
`and 44 pass respectively through the apertures 12 and 22 of
`the drums 10 and 20. From FIG. 2, it will be appreciated that
`output drum 20 is located adjacent wall 42, with the cord
`spool 30 located outwardly therefrom.
`A spring is illustrated at 45 and is coupled between
`storage drum 10 and output drum 20. The spring itself will
`be described later. The spring motor unit 40 also includes a
`pair of surfaces 46 and 47, which are parallel to one another
`and perpendicular to surface 42, defining a generally
`U-shaped enclosure for the two drums and the cord spool. A
`hole 49 is provided in surface 46 and a hole 50 is provided
`in surface 47, with lifting cords 52 shown passing through
`each toward the cord spool 30. The illustrated motor unit 40
`also includes another bracket component 55 spaced apart
`from surface 47 and including a plurality of slots 56 in its
`upper edge. Solid and dashed lines illustrate how the slots 56
`may be used to increase the tension on the cord 52 travelng
`through portion 47 toward cord spool 30.
`Finally, two attachment areas 57 and 59 are shown in FIG.
`2, with holes 58 and 60, respectively. The latter are used for
`attachment of the bracket to the blind head bracket. Obvi-
`ously, the location of the mounting holes can vary widely,
`depending on the overall configuration of the blind with
`which the spring force motor unit 40 is to be used.
`Before proceeding to more detailed descriptions of the
`springs 45, reference should now be made to FIG. 3,
`showing schematically how a plurality of spring motor units
`40 may be coupled together, e.g. by an elongate bar 62
`rotatably coupled to each of the respective cord spools 30 (or
`by gearing on the drums 10 and 20, not shown). It will be
`appreciated from this drawing, which is from a reverse
`perspective compared to that shown in FIG. 2, that the three
`spring motor units 40 will work in unison and the bar 62 will
`compensate for minor variations in spring forces which may
`exist for the individual springs 45 and ensure an even
`winding of the cords 52, even if the force to raise or lower
`the blind is applied off-center.
`Proceeding next to the descriptions of FIGS. 4A and 4B,
`a preferred spring 70 is shown, again in perspective form.
`Spring 70 includes a first narrower end 72, a second wider
`end 74 and a coupling extension 75 having a hole 76 therein.
`The illustrated spring has a constant thickness. Spring 70, in
`use, is wound onto the storage drum in the configuration
`illustrated in FIG. 4B, i.e. with its narrower end coupled to
`body portion 14, and its wider end toward the outside. The
`extension 75 is attached to the body portion 24 of output
`drum 20 using hole 76 and any suitable fastener. The spring
`is wound from one drum to the other in an opposite coil
`orientation. In other words, as spring 70 is transferred from
`the storage drum 10 to the output drum 20, the width of the
`spring 70 between the two drums will decrease and the
`spring will be wound oppositely to its original coil shape.
`Another embodiment of a spring useful in the invention is
`shown in FIGS. 5A and 5B, i.e. a spring 80 having a varying
`thickness. Spring 80 has a thinner first end 82, a thicker
`second end 89 having a width equal to that of end 82, and
`a coupling extension 85 having a hole 86 therein. The
`preferred coil orientation for spring 80 is shown in FIG. 5B,
`this time with the thinner end 82 at the core of the storage
`drum 10 and the thicker end 89 extending onto and around
`the output drum 20, using coupling extension 85 and hole
`86. Again, the orientation of the spring, as it is transferred
`from the storage drum 10 to the output drum 20, is reversed.
`While it has been mentioned earlier that springs of
`different configurations may be employed for variable force
`spring motors, it will now be more fully appreciated that one
`
`10
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`25
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`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`6
`variation would be to use a spring which varies both in width
`and thickness. Also, a coil spring of circular cross-section or
`a laminated spring could be employed. The cross-section
`increasing from the end attached to the storage drum 10 to
`the end attached to the output drum 20.
`
`Proceeding now to FIG. 6, the use of a spring motor unit
`40 for a blind system 90 is shown. Blind system 90 includes
`a bottom bar 92, a headrail 94, and a plurality of slats 95
`located therebetween. The ladders are not illustrated in these
`FIGURES but are conventional and, in and of themselves,
`
`do not form part of the present invention. The cords for
`raising and lowering bottom bar 94 are illustrated at 96 and
`97 and are shown extending through the slats and toward the
`cord spool 30, which will be fully wound with cord when the
`blind is in the position illustrated in FIG. 6. Moreover, the
`storage drum would be wound with most of spring 45 and
`the output drum would be wound only to the extent desirable
`to attach its end and to provide the desired holding force.
`
`Referring now to FIG. 7, the bottom bar 92 is shown in its
`fully lowered position with the individual slats 95 spaced
`from one another and with the cords 96 and 97 unwound
`
`the slats would be
`this point,
`from cord spool 30. At
`individually suspended from ladders (not shown) attached to
`the headrail 94, so that their weight is not being carried by
`the spring motor unit 40. It can be observed that the spring
`45 has been substantially transferred from the storage drum
`10 to the output drum 20, thereby decreasing the amount of
`force exerted on the bottom bar. In an ideal situation, the
`spring force will be just sufficient to prevent bottom bar 92
`from self~raising.
`When it is desired to open blind system 90, the bottom bar
`92 is urged toward headrail 94, resulting in a spring driven
`rotation of the cord spool to wind cords 96 and 97. The
`spring will rewind back to storage drum 10, with an ever
`increasing level of force as the weight of the bottom bar 92
`and accumulating slats 95 continues to increase. The opera—
`tion is completed when the FIG. 6 configuration is achieved.
`While the present invention has been described in con-
`nection with several illustrated embodiments, further varia-
`tions may now be apparent. For example, instead of using
`only two cords (illustrated as 96 and 97 in FIGS. 6—7),
`additional cords could be used for wider blinds, as required.
`In connection with experiments done to date, one suitable
`spring is made from Type 301 High-Yield Stainless Steel
`and has a length of 87 inches and a constant thickness of
`0.005 inches. Its width increased from 0.110 inches at its
`narrow end to 0.312 inches at its wide end. For a coil
`
`diameter of 0.540 inches, a theoretical maximum torque of
`0.650 pounds per inch was created, and the theoretical
`torque minimum was 0.230 pounds per inch.
`In another example, a spring strip of the same length and
`material varied in thickness from 0.0029 inches to 0.0054
`inches with the same coil diameter. The theoretical maxi-
`
`mum torque was O.819 pounds per inch, while the torque at
`the bottom (minimum) is reduced to 0.140 pounds per inch.
`It can be seen from these examples that the spring motor
`provides a variable force which is consistent in application,
`depending upon the particular position of the bottom rail or
`member with respect to the headrail. The theoretical forces
`may be readily calculated using formulas which are avail;
`able from spring manufacturers in which the output force is
`determined by the formula:
`
`Norman Int. Exhibit 1004 Page 7
`
`Norman Int. Exhibit 1004 Page 7
`
`

`

`5,531,257
`
`8
`
`24.,2
`
`where:
`
`F=Output force
`E=Modulus of elasticity
`b=Width of spring strip
`s=Thickness of spring strip
`r=Constant coil radius.
`It then becomes apparent that as the width or thickness
`varies from end to end of the strip, so also will the resultant
`force.
`
`FIGS. 8A and 8B show yet another embodiment of the
`present invention, this time where the spring 45 is a constant
`cross-section spring 110 having'a first end 112, a second end
`114, an extension 115 extending from the second end, and a
`hole 116 in the extension. The coiled form of spring 110 is
`shown in FIG. 8B.
`It has been found that in some applications, for example
`applications where the blinds are short, or are made from
`very light materials, or where friction imparting devices are
`used with the cords that a constant force spring may be
`entirely suitable. This is true because while the weight
`exerted on the lifting cords 96 and 97 will vary as the blind
`is raised and lowered, frictional forces are present which can
`be suflicient to maintain the shade in any desired position
`without free fall. This particular embodiment could be
`enhanced using the friction imparting devices discussed in
`connection with FIG. 2. Accordingly, it can be readily seen
`that the present invention has extremely wide application
`and that the designer may make numerous choices depend-
`ing upon the particular size of the blind, its construction
`materials, etc.
`As with the other embodiments, several spring motors
`employing springs 110 can be coupled together, e.g. as is
`shown in FIG. 3. Alternatively, a plurality of such motors
`may be used which are not interconnected to one another.
`FIG. 9 is a view, similar to FIG. 6, showing in schematic
`form a motor system for raising and lowering a blind. 'In
`order to facilitate understanding of the invention, like ele-
`ments will be identified by like reference numerals in FIG.
`9 and FIG. 6. Accordingly, in FIG. 9, a blind system 90 is
`illustrated having a spring motor unit 40 and cords 96,97 for
`raising and lowering bottom bar 92.
`Also shown in FIG. 9 are a drive motor 130, and a control
`unit 132 for controlling operation of drive motor 130. Drive
`motor 130 is preferably an electrical motor which can drive
`in two directions and is operatively coupled with spring
`motor unit 40 by a coupling 131 to apply a drive force in
`either of two directions to move bottom bar 92 up or down.
`It is advantageous to use both spring motor unit 40 and drive
`motor 130 so that the force applied to blind system 90 by
`spring motor unit 40 augments and assists drive motor 130.
`Drive motor 130 may be operatively coupled anywhere in
`the driving mechaniSm of blind system 90. By such an
`arrangement a smaller, cheaper, and more energy-efficient
`drive motor 130 may be more advantageously employed
`with blind system 90 than could be employed alone without
`spring motor unit 40.
`Control commands may be provided to control unit 132
`for controlling operation of drive motor 130 from a remote
`position by hard—wired connection (not shown in FIG. 9) to
`a remote control unit such as remote control unit 134. In the
`alternative, remote control unit 134 may wirelessly commu-
`nicate with control unit 132 by any of several methods, such
`as sonic coded signal patterns or optic coded signal patterns.
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`The coding patterns may be coded transmission patterns, or
`coded frequency patterns, or combinations of such patterns.
`In environments where there are a plurality of blind
`systems 90 which should be individually wirelessly control-
`lable by one or more remote control units 134, respective
`blind systems 90 must be individually addressable. The
`required distinction among such a plurality of blind systems
`90 may be encoded in each respective control unit 132 and
`recognized by remote control unit(s) 134 in any of several
`manners. For example, respective control units 132 may be
`user-coded by individual digital switches to assign a user-
`determined code to each respective blind system 90. Further,
`similar coding may be efi‘ected by embedding code in a read
`only memory (ROM) in each respective control unit 132, or
`by programming a code into a random access memory
`(RAM) in each control unit 132. A pin grid array or a jumper
`wire arrangement would also accomplish the desired coding,
`but such arrangements are susceptible to error and occupy
`large amounts of space.
`Remote control unit 134 may similarly be encoded to
`selectively address a particular blind system 90: digital
`switch coding, ROM, RAM, and jumper-wiring may all be
`appropriate. Yet another approach involves factory prepro-
`gramming of systems. For example, a factory-provided
`library of codes may be programmed'into a ROM in a
`remote control unit 134. A user may select a code from the
`library of codes for assignment to a respective blind system
`90 by any of the above-described encoding mechanisms:
`e.g., digital switches, RAM, or the like. The user-selection
`may involve merely a two-digit entry or selection to identify
`an eight-digit
`(for example) digital code. By such an
`arrangement, the security of eight-digit coding and its pro-
`tection against inadvertent operation of blinds is achieved
`with significantly less opportunity for errors in user—coding
`since the user needs only to enter two digits to identify/
`encode a particular blind system 90.
`So while the invention has been described in connection
`with certain illustrative examples, it is not to be limited
`thereby but is to be limited solely by the scope of the claims
`which follow.
`What is claimed is:
`
`1. A window covering of the type including a headrail, a
`bottom rail and window covering material located therebe—
`tween, the bottom rail being moveable between a fully raised
`and a fully lowered position with respect to the headrail and
`intermediate positions, the improvement comprising:
`a spring motor located near the headrail and including a
`cord spool;
`at least two cords coupling the bottom rail to the cord
`spool;
`the spring of the spring motor coupled to the cord spool
`'to exert spring forces upon the spool as cord is wound
`therefrom and wound thereon, the spring being an
`elongate spring which moves from a first to a second
`spring storage drum and which is selected to. have
`suificient spring force to essentially balance the bottom
`rail against movement when the bottom rail is in any
`position; and
`an electric motor coupled to the spring motor and adapted
`for selectively rotating the cord spool thereof to raise or
`lower the window covering.
`2. The window covering of claim 1 wherein the spring is
`a constant force spring.
`3. The window covering of claim 1 comprising more than
`one spring motor, at least one pull cord being coupled to the
`cord spool of each spring motor.
`4. The window covering of claim 3 wherein each cord
`spool is coupled to each other cord spool to ensure the same
`
`Norman Int. Exhibit 1004 Page 8
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`Norman Int. Exhibit 1004 Page 8
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`5,531,257
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`9
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`amount of rotation for each cord spool when any cord spool
`is rotated.
`5. The window covering of claim 1 wherein a means for
`imparting friction is provided for at least one cord.
`6. The window covering of claim 1 wherein the motor is
`a DC. motor.
`7. The window covering of claim 1 wherein the motor is
`battery powered.
`8. The window covering of claim 1 wherein the motor is
`a remote controlled motor.
`9. The window covering of claim 1 therein the spring is
`a consistent variable force spring motor and further includes
`an electric motor coupled to the spring motor and arranged
`for rotating the cord spool thereof.
`10. The window covering of claim 9 wherein the motor is
`a DC. motor.
`11. The window covering of claim 9 wherein the motor is
`battery powered.
`12. The window covering of claim 9 wherein the motor is
`a remote controlled motor.
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`13. The window covering of claim 1 wherein the material
`is shade material.
`14. The window covering of claim 1 wherein the material
`is a plurality of mini~blind slats.
`15. A mini—blind including a headrail, a bottom rail and a
`plurality of slats located therebetween, the bottom rail being
`moveable between a first raised position and a second
`lowered position, the slats being held within spaced apart
`mini-blind ladders, the improvement comprising:
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`at least two cords extending from the bottom rail to the
`headrail;
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`a spring motor located in the he adrail and including a cord
`spool, the cords being coupled to the cord spool, the
`spring motor having one storage and one output drum,
`the spring being elongated and moving from the spring
`storage drum to the output drum, or vice-versa, as the
`cord spool is rotated, the spring balancing the bottom
`rail when it is in its first position, its second pos