June 27, 1967
`
`A. STRAHM ET AL
`
`VENETIAN BLINDS
`
`3,327,765
`
`Filed June 29, 1965
`
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`June 27, 1967
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`A.STRAHM ETAL
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`3,32 7,765
`
`2 Sheets-Sheet 2
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`VENETIANV BLINDS
`
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`Filed June 29,
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`1965
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`
`

`

`United States Patent Office
`
`3,327,765
`Patented June 27, 1967
`
`1
`
`3,327,765
`VENETIAN BLINDS
`Andre Strahm, 2 Rue du Quai, Montreux, and· Hans
`Oppliger, 3 Chemin de Verney, Polly, Switzerland
`Filed June 29, 1965, Ser. No. 468,003
`Claims priority, application Switzerland, June 29, 1964,
`8,494/64
`7 Claims. (CI. 160-168)
`
`5
`
`2
`FIG. 7 is a section taken along the lines 7-7 in FIG. 6.
`The blind shown in FIG. 1 comprises a number of
`parallel slats 1 which are shown only in part; the slats 1
`are borne by two flexible ladders 2 suspended on a tilt-
`ing mechanism adapted to vary slat inclination. This
`mechanism comprises in known manner rockers 3 dis(cid:173)
`posed on an operating shaft 4, the rockers 3 altering their
`inclination in accordance with the hand to which the
`shaft 4 is rotated. In FIG. 2, the solid lines show a
`10 midway angular position of the slats 1 and the chain(cid:173)
`dotted lines show the slats in an upright position corre(cid:173)
`sponding to •closure of the blind.
`A bottom cross-member 5 of the blind is retained by
`two pull-tapes 6 which serve to raise the blind. The
`15 tapes are wound around the two drums disposed in a
`raising mechanism received in a box 7 secured to a
`~late 8 disposed at the top of the window opening. The
`tapes 6 aPe secured to the cross member or cross-piece
`5 by adjustable connecting means 9 and extend through
`20 transverse slots 10 in the slats 1, as can be gathered
`from FIG. 4.
`The slots 10 are perpendicular to the slat longitudinal
`axis X-X; slot length L transversely of the slat is
`greater than the width M of the tapes 6, in order that the
`25 slats may be inclinable. On the other hand, slot width
`N lengthwise of the slat is little greater than tape thick(cid:173)
`ness, so that the slots 10 form narrow guides which help
`to reduce twisting of the tapes. The tapes 6 are therefore
`guided angularly at close intervals and cannot therefore
`30 twist themselves when slackened; instead, they just take
`up a sinuous .shape as indicated by the reference 6'
`in FIG. 3.
`The ra:ising mechanism shown in FIGS. 5 and 6 com(cid:173)
`prises two drums 11, 12 rotatable on cylindrical bearing
`surfaces 13 of a cross-spindle 14 disposed between two
`side uprights 15 and 16. The spindle 14 has a •central
`part 17 formed with an aperture acting as a bearing for
`the shaft 4, and the drums 11, 12 are rigidly connected
`to face or bevel gears 11', 12' meshing with a bevel gear
`40 18 freely rotatable on the shaft 4. The bevel gear 18
`is connected to a drive sleeve 19 via a coupling compris(cid:173)
`ing a helical spring 21, half of which engages over a
`cylindrical bearing surface 18' of the gear 18 while half
`engages over a cylindrical bearing surface 19', of the
`sleeve 19. The hand ·of winding of the spring 21 is such
`that the .same tightens and clamps the sleeve 19 and
`gear 18 when the sleeve 19 rotates to the hand corre(cid:173)
`sponding to a raising of the blind, as indicated by an
`arrow A (FIGS. 5 and 6), each tape 6 being wound
`on its respective drum; when the spring 21 opens, it
`can slip as the sleeve 19 is driven in the opposite direc-
`tion (arrow B) ·corresponding to a lowering of the blind.
`On the outside surface of each drum 11, 12 are six
`abutments 22 in the form of raised feet in the drum wall,
`the feet being uniformly distributed around the axis of
`rotation of each drum. Disposed opposite the drum 11 is
`a locking lever 23 rotatable on a pivot 24 rigidly con(cid:173)
`nected to the upright 15. A rear arm 25 of the lever 23
`has a lateral lug 25' which bears against the horizontal
`run of the tape 6a which winds amund the drum 11. A
`front arm 26 of the lever 23 has a projection 26' adapted
`to co-operate with the abutments 22 to prevent the drum
`11 from rotating. While the horizontal tape portion 6a
`stays pulled, the locking lever 23 is retained in an angular
`65 position in which it is away from the range of the abut(cid:173)
`ments 22. When the tape 6a slackens due to the presence
`of an obstacle on the path of the botttom cross-member
`5 of the blind as the same descends, a spring 27 moves
`the lever 23 clockwise in FIG. 5, the projecting part 26'
`70 on the lever then engaging below one of the abutments
`22 to stop the drum from rotating. The presence of the
`
`The present invention relates to a slatted blind com(cid:173)
`prising a flexible pull member to which a bottom cross(cid:173)
`member of the blind is suspended and which is wound
`around a drum rotatable to either hand to raise and
`lower the blfud.
`As a rule, blinds of this kind have metal ·or plastics
`slats which are mounted parallel with <me another on
`flexible ladders, for instance, of textile material, the
`ladders being suspended on a tilting mechanism for
`varying slat orientation. The pull members, at least two
`of which are normally provided, are metal or plastics
`cables or tapes. The pull members of the known blinds
`slacken if an obstacle prevents the blind from being
`lowered, possibly with the result that the pull members
`may be accidentally twisted so that the blind becomes
`unserviceable.
`It is one object of the present invention to provide a
`blind free from this disadvantage.
`It is another object of the present invention to provide
`a raising and lowering mechanism for a blind and in(cid:173)
`cluding a brake which operates to brake the rate of
`descent of the blind, .so that it can be lowered in a
`controlled manner, but which is automatically released
`during raising of the blind so that raising can be per(cid:173)
`formed with the minimum of effort.
`It is a further object of the present invention to prevent 35
`overloading of the pull-tapes for raising the blind, when
`the blind is fully raised.
`It is yet a further object of the present invention to
`prevent surplus lengths of the pull-tapes being released
`if lowering of the blind is obstructed.
`It is also an object of the present invention to prevent
`uneven lowering of the blind whereby one lower end
`of the blind can drop its full distance when the descent
`of the other lower end of the blind is obstructed.
`It is still another object . of the present invention to 45
`prevent overloading of the pull-tapes, should raising of
`the blind be obstructed.
`It is yet a further object of the present invention to
`provide a universal mechanism for winding and unwind-
`ing the pull-tapes of the blind and which can be incor- 50
`porated into any blind irrespective of its slat length.
`It is still a further object of the present invention to
`provide a blind wherein twisting of the pull-tapes during
`raising and lowering is minimised, and the opacity of
`the blind when in the "closed" state is improved.
`With these and other objects in view whkh will be(cid:173)
`come apparent from the following deta:iled description,
`the present invention will become apparent in conjunc(cid:173)
`tion with the accompanying drawings in which:
`FIG. 1 is a diagrammatic view of a blind in eleva- 60
`tion;
`FIG. 2 is a section through the lower left-hand por(cid:173)
`tion of the blind of FIG. 1, taken from the left and
`along the lines 2--2 in FIG. 3;
`FIG. 3 is a section through FIG. 2 taken along the
`lines 3-3 of FIG. 2;
`FIG. 4 is a section along the lines 4-4 of FIG. 3;
`FIG. 5 is a partial elevation view of a blind-raising
`mechanism, to a larger scale than that shown in FIG. 1;
`FIG. 6 is a .section taken along the lines 6-6 of
`FIG. 5; and
`
`55
`
`Norman Int. Exhibit 1003
`
`

`

`3,327,765
`
`10
`
`3
`coupling 20, which slips when the sleeve 19 rotates to the
`hand, indicated by the arrow B, corresponding to a low(cid:173)
`ering of the blind, means that immobilisation of the drum
`11 by the lever 23 does not prevent rotation of the sleeve
`19, the s-ame slipping inside the spring 21 which tends to 5
`open. A second locking lever 28 devised similarly to the
`lever 23 locks the drum 12 when the tape portion 6b
`thereon slackens. Consequently, a slackening of either
`tape 6 automatically causes a locking of the two drums
`11, 12 which are coupled together via the gear 18.
`At is right-hand end (FIGS. 5 and 6) the sleeve 19
`has a cylindrical bearing surface 29 which is engaged in
`a helical spring 30 engaging over a cylindrical bearing
`surface 31 of a sleeve 32 freely rotatable on the shaft 4.
`The sleeve 32 has a shoulder 32' and two conical washers 15
`or the like 33 are axially clamped between the shoulder
`32' and the left-hand surface of a transverse wall 34
`disposed between the uprights 15 and 16 (FIG. 6). A
`screwthreaded ring 35 screwed on the sleeve 32 forms a
`shoulder for two conical washers or the like 36 which are 20
`clamped axially between the ring 35 and the right-hand
`surface of the wall 34. The ring 35 is so screwed on the
`sleeve 32 as to considerably compress the conical washers
`33, 36 forming a friction brake between the stationary
`wall 34 and the rotatable sleeve 32. The spring 30 forms 25
`a one-way coupling between the sleeves 19 and 32 and
`is wound in a sense such that there is a rigid connection
`·between the sleeves 32 and 19 when the sleeve 19 rotates
`in the direction indicated by the arrow B, corresponding
`to a lowering of the blind, whereas the coupling slips 30
`when the sleeve 19 rotates to the hand indicated by the
`arrow A, corresponding to the blind being raised. The
`brake therefore operates only during the descent of the
`blind and is automatically cut out of operation during the
`raising of the blind.
`The raising mechanism also comprises provision for
`interrupting the rotation of the drums 11 and 12 in the
`sense of a winding-up of the tapes 6 when the blind
`reaches a predetermined top position. Accordingly, the
`free end of the spring 21 is bent to form a finger 37 40
`engaged in a recess 39 in the left-hand end (FIGS. 5 and
`6) of a sheath 40 engaging over the sleeve 19. The sheath
`40 has a castellated ring 41 (FIG. 7). The sheath 40 is
`normally free to rotate with the sleeve 19 and can be
`prevented from rotating in the direction A, corresponding 45
`to the blind being raised, by a vertically movable bolt 42
`which is operated automatically when the blind has
`reached its top position. The bolt 42 is formed with an
`oblong aperture 43 for engagement on a hearing surface
`44 of the sleeve 32, is guided by a pin 45 sliding in a slot 50
`46 in the wall 34, and has a lateral projection 47 engage(cid:173)
`able in the teeth 41. The .projection 47 (FIG. 7) has a
`front abutment surface 47a which is disposed radially in
`relation to the axis of r-otation of the sheath 40, the pro(cid:173)
`jection 47 also having a rear inclined surface 47b which 55
`forms an inclined cam. The bolt 42, normally retained
`by a spring 48 in the bottom position shown in FIG. 5,
`is adapted to be raised by the blind slats when the blind
`is moved to its raised position. Accordingly, the bottom
`part 49 of the bolt 42 extends below the raising mecha- 60
`nism casing on the path of the top slat of the blind.
`When the bolt 42 rises because the slats have reached
`the top position, surface 47a of the projection 47 engages
`in the teeth 41 to prevent the sheath 40 from continuing
`to rotate in the direction indicated by the arrow A (FIG. 65
`7). The spring 21, being retained by its finger 37, cannot
`continue to follow the rotation of the sleeve 19 in the
`direction of the arrow A (blind rising). The spring 21
`therefore slips on the surface 19' so that, although the
`sleeve 19 continues to rotate, the drive to the drums 11, 70
`12 is interrupted automatically. At the start of the next
`descent, however, the inclination of rearward surface 47 b
`of the projection 47 enables the sheath 40 to rotate back(cid:173)
`wards (arrow B, blind descending); during the descent
`the bolt 42 is thrust back resiliently when the first tooth 75
`
`4
`of the teeth 43 passes by. The bolt 42 then resumes its
`bottom position, releasing the sheath 40 and allowing the
`blind to descend normally.
`The sleeve 19 is wtated by the shaft 4 via a pin 51
`secured therein. As can be gathered from FIG. 7, the pin
`51 is received in recesses 52 in the sleeve 19 so that the
`coupling thus formed has an idle travel of approximately
`one right-angle, an amount corresponding to the opera(cid:173)
`tion of the rockers which are also disposed ·on the shaft 4.
`The shaft 4 can be driven either by a crank or by a
`motor. It has a central portion 4a which extends through
`the raising mechanism box, and two lateral portions 4b,
`4c which are disposed on either side of such box and
`which are connected to the central portion 4a by readily
`demountable sleeves 53 (FIGS. 1 and 6). After the latter
`sleeves have been dismantled the raising mechanism cas-
`ing can be removed for inspection or repair without any
`need to dismantle the two shaft lateral portions on which
`the blind is suspended.
`The raising mechanism in the casing 7 can be used for
`blinds of various widths, the length of the shaft lateral
`portions being modified correspondingly. For very wide
`or very heavy blinds, the rpull tapes can be arranged to
`run over guide pulleys placed on the bottom cross(cid:173)
`member 5 or to the plate 8, so that a pulley block is
`provided between these items. The chain line in the left-
`hand part of FIG. 1 shows how such a pulley block can
`be constructed; the tape connection place is shifted to 54
`and an extra guide pulley is mounted on the bottom cross(cid:173)
`member 5 at 55.
`The blind shown has the following advantages:
`The brake 32 is "off" for ascent, so that relatively little
`torque is required.
`At the end of ascent the coupling 20 disengages auto-
`35 matically, so that the pull tapes cannot be overloaded.
`During descent the drums 11, 12 stop automatically if
`the pull tapes slacken. The operating shaft can still con(cid:173)
`tinue to rotate without difficulty and the stop devices oper(cid:173)
`ate at the end of descent, when the blind is fully extended,
`as well as if an accidental obstacle is placed on the path
`of the blind.
`The raising mechanism received in the central casing 7
`can readily be used to operate ·blinds of various sizes.
`Inter alia a number of pull tapes can be provided on each
`of the two drums of the system, in which event the tapes
`on any one drum wind up simultaneously thereon one
`upon another.
`. The slots with which the slats are formed for the tapes,
`m the form of thin transverse slots, guide the tapes satis(cid:173)
`factorily and also reduce the perforate surface of the slat
`so that the darkening effect provided by the blind is im~
`proved.
`The features hereinbefore described and shown in the
`drawings obviate any risk of the pull tapes being over(cid:173)
`loaded and ensure that the pull tapes are always kept in
`tension and are guided satisfactorily.
`While we have disclosed several embodiments of the
`present invention, it is to be understood that these em(cid:173)
`bodiments are given by example only and not in a limit(cid:173)
`in? sense, the sc~pe of the present invention being deter(cid:173)
`mmed by the objects and the claims.
`We claim:
`1. A venetian ·blind comprising a horizontal top mem(cid:173)
`•ber, fiex!ble support means depending from said top mem(cid:173)
`ber, honzontal spaced parallel slats carried •by said support
`means, flexible pull means depending from said top mem-
`ber, a horizontal bottom member disposed beneath the
`lowermost slat and connected to the lower portions of said
`support means and said pull means, a blind raising and
`lowering mechanism mounted on said top member, drum
`means disposed in said mechanism and around which the
`upper end-portions of said .flexible pull means are wound,
`drive means for rotating said drum means selectively in
`opposite directions to raise and lower the blind respec(cid:173)
`tively, blocking means mounted on the top member
`
`Norman Int. Exhibit 1003
`
`

`

`3,327,765
`
`5
`and operatively movll!ble between a first position at which
`rotation of said drum means by the drive means is per(cid:173)
`mitted and a second position at which it interrupts the
`transmission of drive from said drive means to said drum
`means, a bias element urging said blocking means to its 5
`first position, and a bolt member on said blocking means
`and disposed in the path of terminal movement of the bot(cid:173)
`tom member to its highest position where·by said terminal
`movement shifts the bolt member against the bias element
`to move the blocking means from its first position to its 10
`second position so that further rotation of the drum means
`is prevented.
`2. The blind set forth in claim 1, in which said drive
`means includes a shaft and clutch means operatively con(cid:173)
`necting the shaft to the drum means, and said bolt member 15
`is operatively connected to the clutch means and drum
`means and holds the clutch means disengaged and the
`drum means in its final position as long as the bottom
`member is in said highest position.
`3. The blind set forth in claim 1, in which said drive 20
`means includes a shaft, clutch means operatively con(cid:173)
`necting the shaft to the drum means, a drive part of said
`clutch means mova'ble with the shaft, a driven part of said
`clutch means movable with said drum means, an elongated
`coil spring frictionally engaging said drive part and said 25
`driven part and rotatable to transmit drive therebetween
`during blind raising, a sleeve rotatable on said shaft and
`formed with an anchorage, a finger on said spring and
`held in said anchorage so that the spring and sleeve move
`together, and a castellated peripheral surface on said 30
`sleeve providing abutments selectively engaged by the bolt
`member when the bottom member is in said highest ,posi(cid:173)
`tion to prevent further rotation of the spring.
`4. A venetian blind comprising a top member, flexible
`support means depending from said top member, hori- 35
`zontal vertically-spaced parallel slats carried by said sup(cid:173)
`port means, first and second flexible pull means depend-
`ing from opposite end-portions respectively of said top
`member, a horizontal bottom member di&posed beneath
`the lowermost slat and connected to the lower portions of 40
`said support means and said first and second pull means,
`a blind raising and lowering mechanism mounted on said
`top member, two drums disposed in said mechanism and
`around which the upper end-portions of said first and
`second flexible pull means are res·pectively wound, a face 45
`gear formed on each drum, a drive shaft extending through
`said mechanism between the drums and lying in a plane
`parallel to the hanging plane of the blind, a hub freely(cid:173)
`rotatable on said drive shaft, a third face gear .formed on
`said hub about the shaft axis and meshing with the two 50
`drum face gears, and a coil spring frictionally engaging
`the hub and providing a coupling for transmitting drive
`thereto from the drive shaft.
`5. A venetian blind comprising a top member, flexible
`ladders depending from said top member, vertically spaced 55
`rungs on said ladders, horizontal spaced parallel slats en(cid:173)
`gaging between the rungs of said ladders, slots formed
`in said slats and extending ·perpendicularly of the longi(cid:173)
`tudinal axes of the slats, pull-tapes extending downwardly
`through said slots which are longer than the pull-tape 60
`widths but are only marginally wider than the pull-tape
`thicknesses, a bottom member connected to the lower ends
`of said ·pull-tapes and said ladders, rocker means connected
`to the upper ends of said ladders, means controlling said
`rocker means to adjust the tilt angle of the slats about 65
`said axes, a ·blind raising and lowering mechanism mount-
`ed on said top member, drum means disposed in said
`mechanism and around which the upper end-portions of
`said 'pull-tapes are wound, drive means for rotating the
`drum means selectively in opposite directions to raise and 70
`lower the blind, respectively, means Tesiliently engaging
`the pull-tapes, stop means operatively connected between
`said resiliently engaging means and said drum means, bias
`means resisted ·by the tension of the pull-tapes and acting
`to force said stop means into stopping engagement with 75
`
`6
`the drum means in the event of the pull-tapes becoming
`slack, blocking means mounted on said top member and
`operatively movable ·between a .first position at which ro(cid:173)
`tation of said drum means by said drive means is per(cid:173)
`mitted and a second position at which it interrupts the
`transmission of drive .from said drive means to said drum
`means, a bias element urging said blocking means to its
`first position, and a bolt member on said blocking means
`and &;.posed in the path of terminal movement of the
`bottom member to its highest position whereby said ter(cid:173)
`minal movement shifts the bolt member against· the bias
`element to move the blocking means from its first posi(cid:173)
`tion to its second position, so that further rotation of
`the drum means is prevented.
`6. A venetian blind comprising a top member, flexible
`ladders depending from said top member, vertically spaced
`rungs on said ladders, horizontal spaced parallel slats en(cid:173)
`gaging between the rungs of said ladders, slots formed in
`said slats and extending perpendicularly of the longitu(cid:173)
`dinal axes of the slats, pull-tapes extending downwardly
`through said slots which are longer than the pull-tape
`widths but are only marginally wider than the pull-tape
`thicknesses, a bottom member connected to the lower ends
`of said pull-tapes and said ladders, rocker means connect(cid:173)
`ed to the upper ends of said ladders, means controlling
`said rocker means to adjust the tilt angle of the slats about
`said axes, a blind raising and lowering mechanism mount(cid:173)
`ed on said top member, drum means disposed in said
`mechanism and around which the upper end-portions of
`said pull-tapes are wound, drive means for rotating the
`drum means selectively in opposite directions to raise and
`lower the blind, respectively, means resiliently engaging
`the pull-tapes, stop means operatively connected between
`said resiliently engaging means and said drum means, bias
`means resisted by the tension of the pull-tapes and acting
`to force said stop means into stopping engagement with
`the dTUm means in the event of the pull-tapes becoming
`slack, blocking means mounted on said top member and
`operatively movable between a first position at which rota(cid:173)
`tion of said drum means .by said drive means is permitted
`and a second position at which it interrupts the transmis(cid:173)
`sion of drive from said drive means to said drum means,
`a bias element urging said blocking means to its first posi(cid:173)
`tion and a bolt member on said blocking means disposed
`in the path of terminal movement of the bottom member
`to its highest position whereby said terminal movement
`shifts the bolt member against the bias element to move
`the blocking means from its first position to its second
`position so that further rotation of the drum means is
`prevented, friction brake means disposed on said top mem(cid:173)
`ber, and a unidirectional coupling connecting the friction
`brake means to brake the drum during blind lowering
`while disconnecting said friction brake means from the
`drum means and drive means during blind raising.
`7. A venetian blind comprising a top member, flexible
`ladder depending from said top member, vertically spaced
`rungs on said ladders, horizontal spaced parallel slats en(cid:173)
`gaging between the rungs of said ladders, slots formed
`in said slots and extending perpendicularly of the longi(cid:173)
`tudinal axes of the slats, pull-tapes extending downward(cid:173)
`ly through said slots which are longer than the pull-tape
`widths but are only marginally wider than the pull-tape
`thicknesses, a bottom member connected to the lower
`ends of said pull-tapes and said ladders, rocker means
`connected to the upper ends of said ladders, means con(cid:173)
`trolling said rocker means to adjust the tilt angle of the
`slats about said axes, a blind raising and lowering mech(cid:173)
`anism mounted on said top member, drum means dis(cid:173)
`posed in said mechanism and around which the upper
`end-portions of said pull-tapes are wound, drive means for
`rotating the drum means selectively in opposite directions
`to raise and lower the blind, respectively, means resiliently
`engaging the pull-tapes, stop means operatively connected
`between said resiliently engaging means and said drum
`means, bias means resisted by the tension of the pull-tapes
`
`Norman Int. Exhibit 1003
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`

`

`7
`and acting to force said stop means into stopping engage(cid:173)
`ment with the drum means in the event of the pull"tapes
`becoming slack, blocking means mounted on said top
`member and operatively movable between a first position
`at which rotation of said drum means by said drive means
`is permitted and a second position at which it interrupts
`the transmission of drive from said drive means to said
`drum means, a bias element urging said blocking means to
`its first position, a bolt member on said blocking means
`disposed in the path of terminal movement of the bottom 10
`member· to its highest position whereby said terminal
`movement shifts the bolt member against the bias ele(cid:173)
`ment to move the blocking means from its first position
`to its second position so that further rotation of the drum
`means is prevented, friction brake means disposed on said 15
`top member, a unidirectional coupling connecting the
`friction brake means to brake the drum during blind low(cid:173)
`ering while disconnecting said friction brake means from
`the drum means and drive means during blind raising,
`said drum means comprising two drums individually hav(cid:173)
`ing wound therearound pull-tapes extending opposite ends
`of the blind respectively, a drive shaft forming said drive
`
`DAVID J. WILLIAMOWSKY, Primary Examiner.
`20 REINALDO P. MACHADO, Examiner.
`P.M. CAUN, Assistant Examiner.
`
`3,327,765
`
`8
`means extending parallel to the hanging plane of the blind
`between the two drums, a face gear formed on each drum,
`a hub freely rotatable on said drive shaft, a third face gear
`formed on said hub around the shaft axis and meshing
`5 with the two drum face gears, and a coil spring friction(cid:173)
`ally engaging the hub and providing a coupling for trans(cid:173)
`mitting drive thereto from the drive shaft.
`
`References Cited
`UNITED STATES PATENTS
`211932 Ward ------------ 160-298 X
`12/1941 Ban --------------- 160-170
`7/1966 Griesser ------------ 160-170
`FOREIGN PATENTS
`8/1925 Great Britain.
`
`1,845,856
`2,264,609
`3,260,302
`
`238,426
`
`Norman Int. Exhibit 1003
`
`