Dec. 31, 1946. |_, SQRRENTINO ' 2,413,471 I COUNTERWEIGHT DEVICE FOR ROLLER CURTAINS ~ Filed Nov. 2, 1943 4 Sheets-Sheet 1 _ . E; "Ma I / JW ? n17”, 311mm, Dec. 31, 1946. L. SORRENTINO ~ 2,413,471 vCOUNTERWEIGHT DEVICE FOR ROLLER CURTAINS Filed Nov. 2, 1943 4 Sheets-Sheet 2 L Dec. 31, 1946. ' |_, SORRENTINO I 2,413,471 COUNTERWEIGHT DEVICE FOR ROLLER CURTAINS Filed Nov. 2, 194-3 4 Sheets-Sheet 5 Elthnwmd Dec- 31,1946- |_. SORRENTINO I 2,413,471 COUNTERWEIGHT DEVICE FOR ROLLER CURTAINS Filed Nov. 2, 194a ' " 4 Sheets-Sheet 4 2,413,471 Patented Dec. 31, 1946 UNITED STATES PATENT OFFICE COUNTERWEIGHT DEVICE. FOR) ROLLER . CURTAIN S ' Luis Sorrentino, Buenos Aires, Argentina. ApplicationNovember 2, 1943, Serial n10-50839 7- Claims. ' (Cl.'160—--33) 1. This invention ‘relatesto a‘ counterweight de vice for roller curtains, and more particularly to a counterweight device for facilitating the op eration of opening and closing blinds and the like. Several elements andv devices have been sug gested and. to a certain extent used heretofore for the'purpose of compensating the'weight of. the curtain~during the action-thereof, but‘ inasmuch as" such» devices are generally constituted by springs or‘ simple counterweights, they onlycoun teract theweight in certain’ positions of-‘the blind. Thus, in the caseof relativel'ylarge roller cur tains,» it is‘necessary to use'a reductioncontrol, in the way of combination apparel capable of multiplying» the forces with less speed in' order to mum effort to open and ‘close the blind,» andlalso to graduate and regulate the slats thereof, since thesecondary spiral of said pulley isarranged so, as to act‘ between the positions of maximum spacing. or light and. of juxtaposition of, said slats. A further object of the invention is to simplify the. counterweight and .control mechanism with out vrequiring special. installations. . Astill further object‘of theinvention isto pro vide a deviceoithe kind mentionedlabove, which will render safe the operation of the blind in any position thereof, for which purpose-the control of the device is provided with a crank handle ’ which, on being placed in inoperative position ‘will lock the entire. mechanism. . The. above andotheri objects and‘ advantages of the present invention will‘ become apparent Actual experiments have shown-.that in order from the course of the following. description, to obtainthenecessary equilibriumv of the coun terweight relative to the curtain, it‘ is'necessary 20 when read in'conjunction with the accompanying drawings illustrating the; invention by way of ex that‘ the pulley with which the weight is asso ample and in a preferred embodiment. ciated, shouldvha-veia variable radius, and this is In the‘ drawings: achieved by means of the present invention. Fig; 1‘ is a' front View of'the blind in open posi The device of the present invention comprises‘ av pulley’ counterweight mechanism- wherein‘ the " tion, showing the manner in which same is com overcome the resistanceoft'the‘blind or curtains. winding base of the pulley is- constituted by a‘ spiral groove orv channelthe radius of which in creases gradually fromia'lminimumi section to the maximum periphery “thereof ; andiagain decreases on the opposite facethercof', but’ with a shorter turn capabl‘eofj presenting a’ substantial diiier enceirelative tothe' path of‘the channel corre- sponding'tothe main facev thereof; saidipulley is‘ so combined that while it1 is ?xed' bined with the’ counterweightdevice. Fig. 2 is a side View showing the weight de pending from the channel of smaller section of , the pulley. , Fig. 3' is‘ a View similar to Fig. 1 but showing the blind in closed position, with the slats in spaced relation, at which time the weight of. the counterweight device is acting on the maximum turn of the spiral. . Fig. Zl'shows the same blind'in fully closed posi tion, viz; with the slats juxtaposed and the weight therewith, in sucha' manner that‘ the weight act thereof ‘counterbalanced by the counterweight de ingxby means of its cable in said channel of the pending from the secondary spiral of the pulley. pulley, willbehave as an element of substantially’ Fig; 5’is a cross-sectional view of‘ the winding variable power; depending on the position in which. said. weight is hanging, since the lever 40 ‘drum, taken along the line N——N of Fig. 4. Fig. 6 is a front view of the control device of radius'will be larger‘ orv smaller according t'o'~=the the curtain, with the rosette of'the crank par-_ direction ofzrotatioin Inasmuch as-the diameter‘ tially‘broken away so as to show the diiierent of the'pulley: is calculated in accordance with the :locking points; and weightzofi the icurt'ainto' which the counterweight Fig. 715 a cross-sectional View of the same con device is‘ applied‘, this will" ensure a substantially trol‘d'evicek stable .equilibrium?n every. position of the cur The same reference characters are used to in tain; ' dicate like’ or corresponding parts or elements Apart’ from:v the ; foregoing, the" invention‘ conthroughout the different ?gures. ' templates: other-objects; among‘ whichv may be torthe winding. drum, it will act‘ in combination‘ ‘ citedythe provision of. a counterweight arrange ment» of» relative and" graduali equilibrium throughout the-total ‘opening-p01" closing-positions 0f:the.blind. . . Arfurther objectfof theinventioniis torprovid'e" direct controlimeans‘whichxwill requirea mini~ With reference to the drawings, a'indicates a blind, which in the present instance is consti tuted by a plurality of‘ slats i joined‘ together by link members 2 and forming an» articulated assembly; which: may be‘ wound‘ on a‘ drum‘ 3 to whichzonerend‘ioirtheblin‘diis attached, the‘ latter 2,413,471 3 sliding on a guide 4. 4 . Said drum 3 is ?xed to a shaft 5 mounted on bearings 6 suitably located at each side of the frame in which the blind is to be mounted. In the fully wound position shown in Fig. 1, the blind a o?’ers torque relative to the drum 3, but when the blind is unrolled to the position shown in Fig. 3, the entire weight thereof de pends on the radius of said drum thus necessi— guide the cable with said weight 8 during its travel by the different channels of both the main and secondary spirals. For the purpose of operating the blind, shaft 5 is provided with a bevel gear [3 meshing with a gear l4 having ?xed thereto a toothed wheel l5 which is connected by means of an endless chain IS with a control gear Wheel I1. Said control wheel I‘! is ?xed to shaft [8 tating a counterweight which will counteract the 10 mounted on bearings l9 and 20 located in a box load throughout‘the opening and closing range 2| of the actuating or control device 0 which is of the blind. In the position shown in Fig. 3, the embedded in the wall by means of anchoring slats remain in spaced relation with each other,v members 22. Shaft l8 ends in a rosette 23 hav for ventilation and light purposes. This spacing ing pivoted thereto a crank 25 by means of pivot of the slats may be cancelled through the action 15 24, so that upon displacing said crank 25 to the of the same drum which on further unwinding position shown in full lines in Fig. 7, it will serve the blind will cause the juxtaposition of the slats to rotate the shaft l8 and, through toothed wheel I, thus bringing the blind to a fully closed posi I‘! and chain l 6, said rotary motion will be trans tion as shown in Fig. 4. In this instance, inas much as the slats are superposed relative to each 20 mitted to wheel l5, the gear [4 of which will ac tuate the gear l3 and consequently shaft 5, drum other, the weight of the assembly will not de 3 and pulley I), thus Winding or unwinding the pend on the radius of the drum. blind, depending from the direction in which the According to the present invention, the curtain or blind a is balanced by means of the counter weight device constituted by the pulley b, cable 1 and weight 8. Said pulley b is ?xed to the shaft 5 so as to act simultaneously with the drum 3. As the blind a is closed or opened, the torque will be greater or smaller, which will depend on crank is turned. Upon placing the crank 25 in inoperative posi 25 tion shown in dotted lines in Fig. 7, same is se cured by means of a button 26 arranged at the side of a groove 21 provided diametrically on said rosette 23 so as to accommodate said crank when the latter is in inoperative position, thereby giV ing said rosette the appearance of a simple disc. the portion of the blind depending from the drum Said groove or recess 21 is provided with a pin 3, and therefore. said device should act in rela 28 passing through the body of said rosette 23 tion to the weight'oifered by the depending por and urged by a spring 29 so as to project from tion of the blind. the surface of said recess 21. Upon press For this purpose. said pulley b is spiral-shaped, 35 ing bottom said pin 28, overcoming the resistance of having a channel 9 in which the cable 1 is wound. spring 29, the opposite end 28' thereof will ex As clearly shown in Figs. 1 to 5. said channel 9 is tend outwardly of the rosette and enter one. of spiral-shaped with a helical pitch, that is to say, the holes 30 provided in a cup shaped element 3| that said channel 9, from the largest Or maxi ?xed to the box 2| of the control device 0. Said mum turn 9’ gradually decreases in radius until 40 holes 30 form an annular line. Consequently, it reaches the smallest or minimum turn 9". upon placing the crank 25 in inoperative position Thus, when the Weight 8 depends, through cable as shown in dotted lines in Fig.7, pin 28 is pressed 1, from the maximum turn 9', said weight will so that the end 28' thereof will enter one of said offer an e?ect equivalent to the weight of the holes 30, thereby locking the rosette against curtain a in its fully unwound position, and said 45 movement and, consequently, the ‘entire control channel 9 has a convolution with as many turns as revolutions the drum must eifect in order to fully wind or unwind the blind. Thus, when the mechanism of blind a will be prevented from moving either for opening or closing the blind. Thus, the inoperative position shown in dotted blind is in fully wound or open position, as shown lines in Fig. 7 constitutes a safe means for look in Figs. 1 and 2 the cable 1 of weight 8 will be lo 50 ing the curtain in any position. cated within that portion of the channel corre Upon placing crank 25 in operative position as sponding to the smallest turn 9" so as to be in shown in full lines in the same Fig. 7, said spring equilibrium with the blind which oifers substan tiallv no weight in this position. 29 will act to free the pin 28 from the correspond ing hole 30, thereby releasing the entire mecha Apart from the spiral formed by channel 9, 55 nism and placing same in condition to control said pulley b is provided with a second channel l0 which extends from the maximum turn 9', de scribes a short path and ends at I 0’, this latter spiral channel In constituting an extension oppo the curtain a by means of said crank 25. Resuming, said pulley b with the two spiral channels 9 and l 0, and the associated cable 1 and weight 8, will act as an automatic regulator so as site the main spiral channel 9. Thus, channel 60 to maintain a constant counterweight equilibrium I!) is a secondary spiral but enables the adapta relative to the curtain a, inasmuch as the torque tion of cable 1 so as to reduce the torque exerted olfered by said weight 8 in combination with the by weight 8 in passing from said maximum turn pulley, starting from the smallest turn 9" corre to said secondary spiral. sponding to the fully wound position shown in , The secondary spiral determined by channel 65 Figs. 1 and 2, will be gradual and relative up to l5 serves to reduce the radius arm of the weight the maximum unwinding as shown in Fig. 3, when 8 on pulley b when the drum 3 is further actu the weight of the entire curtain suspended from ated from the position of the blind shown in Fig. the radius of drum 3 is compensated by said 3 to that illustrated in Fig. 4 where the slats are weight 8 which is at this time gravitating on the juxtaposed and, therefore, cease to gravitate on maximum radius of the pulley, that is to say, on the radius of drum 3 until said gravitation is ? nally entirely counterbalanced when all the slats _ the turn 9' thereof. However, if the action of the control mechanism 0 is continued so that the I.. drum 3 will rotate further in the same direction, Said cable ‘I is guided on a sheave ll rotatably mounted on a roll I 2 and slidable thereomisnras to 75 the slats I will superpose, with the consequent l are superposed. torque reduction on the radius of drum 3, while 2,41 31,4:71; 5, 6 sai'diholes being» arranged‘ in anannular line con at~the same time cable ' 11 w~ill' pass- on to the sec centric- to'th'e axis-of rotation of the rosette, a onda'ry» spiral of: channel" ID,- in such a- manner groove-therein, acrank pivoted to the'rosette to thatvupon/ reaching‘theeportion: Hi’, all the slats effect‘v rotation of? said second‘ shaft, said crank I’ will remain superposed-to» each other without offering any torqueand, therefore, in complete beihg-adapted'to befolded inisaid groove when'in inoperative position, a’ spring~urged pin within equilibrium with thecounterweigh‘t; said groove out-of engagement with the holes of ItI-isv evident’ that‘ in'carrying the invention into practice; several changes-and alterations will oc said¥cuplwhenthe crank isin operative position, and? inengagement withone of said'holes when cur to thoseskilledin the art, without departing the crank is in inoperative position in said'groove from the scopeeof the invention as- clearly set 10 and'means'totransmit the rotation‘ of said Sec forth in the appended claims; ondishaft‘toithe-winding- drum of‘ theiroller slat I claim: I 1; A-counter-weight device for a roller slat blind. mounted on a drum supported by a shaft, the slats thereof being connected by means permitting sep aration, said device comprising a spiral pulley mounted on said shaft, a counterweight depend ing from a cable windable on said spiral pulley, the weight of said depending counterweight act blind. a. A counterweight device for a roller slat blind 15 mounted on a drum supported by a shaft com ing over the different radii of said pulley being in equilibrium with the unwound portion of the slat blind in the different winding positions there of on said drum, said pulley having a main spiral corresponding in increasing radii to the radii of the winding roll of said slat blind, and a secondary return spiral continuing from the maximum turn of the main spiral, the decreasing radii of said sec ondary spiral corresponding with the transition from the position of maximum unwinding of the slat blind with the slats in maximum spaced rela tion and the bottom slat just touching a support, , to the position of juxtaposition of the unwound slats whereby the weight of the suspended portion of the blind is substantially counterbalanced by said counterweight. 2. A counterweight device for a roller slat blind mounted on a drum supported by a shaft, the slats thereof being connected by means per mitting separation, said device comprising a spiral prising a spiral pulley mounted on said shaft. a from a cable windable counterweight depending the weight of said depend- ' on said spiral pulley, ing counterweight acting over the different radii of said pulley being in equilibrium with the un wound portion of the slat blind in the different winding positions thereof on said drum, and a control mechanism for said drum comprising a box, bearing members therein, one of said bear ings being in the form of a cup-shaped member and provided with holes, a second shaft in said bearing, one end of said second shaft extending beyond the exterior face of the cup and terminat ing in a rosette, said holes being arranged in an annular line concentric to the axis of rotation of the rosette, a groove therein, a crank pivoted to the rosette to effect rotation of said second shaft, said crank being adapted to be folded in said groove when in inoperative position, means mounted in the groove in said rosette and en gageable in the holes in said cup-shaped member to lock the second shaft and rosette against ro tation, means urging said latter means out of such locking position, said ?rst means being en gageable by said crank when in an inoperative pulley mounted on said shaft, a counterweight de 40 position in the groove to force same into the lock pending from a cable windable on said spiral pul ing position, and means for transmitting the ro ley, a sheave for guiding said cable, said sheave tation of said second shaft to the winding drum being rotatably and transversely slidably mounted of the roller slat blind. on a sheave-shaft, the weight of said depending 5. In a counterweight device for use in control counterweight acting over the different radii of ling a winding drum mounted on a shaft and said pulley being in equilibrium with the unwound adapted to receive a plurality of serially connected portion of the slat blind in the different winding members, a pulley mounted on said shaft, said positions thereof on said drum, said pulley having pulley having a pair of spiral grooves therein, one a main spiral corresponding in increasing radii of said grooves increasing from a minimum up to to the radii of the winding roll of said slat blind, a maximum radius and the other groove decreas and a secondary return spiral continuing from the ing from the same maximum down to a minimum, maximum turn of the main spiral, the decreasing a cable‘attached at one end to the spiral pulley radii of said secondary spiral corresponding with and a counterweight attached to said cable, the the transition from the position of maximum un convolutions of one of said spiral grooves on the winding of the slat blind with the slats in maxi pulley being adapted to increase the radius arm mum spaced relation and the bottom slat just and hence the torque on the shaft as the winding touching a support, to the position of juxtaposi drum is rotated to unroll a greater length of the tion of the unwound slats whereby the weight of serially connected me __bers_ and operating means the suspended portion of the blind is substantially connected to said shaft for rotating same, said ca - counterbalanced by said counterweight. ble being shiftable from the first to the second 3. A counterweight device for a roller slat blind groove for relieving the drum of the weight of the mounted on a drum supported by a shaft compris slats. ing a spiral pulley mounted on said shaft, a coun 6. In a counterweight device for use in con terweight depending from a cable windable on 65 trolling a winding drum mounted on a shaft and said spiral pulley, the weight of said depending adapted to receive a plurality of serially connected counterweight acting over the different radii of members, a pulley mounted on said shaft, said said pulley being in equilibrium with the unwound pulley having a pair of spiral grooves therein, one portion of the slat blind in the different winding of said grooves increasing from a minimum up to positions thereof on said drum, and a control a maximum radius, the second of said grooves de 70 mechanism for said dru-m comprising a box, bear creasing from the same maximum down to a mini ing members therein, one of said bearings being mum, a cable attached at one end to the spiral in the form of a cup-shaped member and provided pulley and a counterweight attached to the cable, ' with holes, a second shaft in said bearing one end a guide roll mounted in parallel relationship to of said second shaft extending beyond the exte said shaft, a sheave slidable on said guide roll, rior face of the cup and terminating in a rosette, 2,413,471, said cable extending over the sheave, the con volutions of one of the spiral grooves on said pulley being adapted to increase the radius arm and hence the torque on the shaft as the winding drum is rotated to unroll a greater length of the serially connected members, and operating means connected to the shaft for rotating same, said 8 shaft, driving connections between the shafts, a. frame member mounting said second shaft, a cir cular row of holes in said frame member concen trically disposed with respect to the second shaft, a rosette of substantially circular shape in said second shaft, a spring urged stop pin mounted in said rosette and adapted to rest in said holes, a cable being shiftable from the ?rst to the second handle of length approximately equal to the di groove for relieving the drum of the-weight of ameter of the rosette, said handle being pivoted the slats. 10 to the rosette adjacent the periphery of the 7. In a control device for a slat-type blind latter and foldable to overlie the stop pin. adapted to be coiled around and un-coiled from a shaft, a second shaft perpendicular to said - LUIS SORREN'I‘INO.