US3102584A

US3102584A - Window shade roller

Info

Publication number: US3102584A
Authority: US
Inventors: Znamirowski Henry
Original assignee: EASTERN PROD CORP
Current assignee: Eastern Products Corp; EASTERN PROD CORP
Priority date: 1961-12-07
Filing date: 1961-12-07
Publication date: 1963-09-03

Description

Sept. 3, 1963 H. zNAMlRowsKl wmnow SHADE: ROLLER 2 Sheets-Sheet 1 Filed Dec. 7, 1961 Sept. 3, 1963 H. zNAMmowsKl WINDOW SHADE ROLLER 2 Sheets-Sheet 2 Filed Dec. 7, 1961 mm NN wm mm mm .vm

United tates arent 3,102,584 WINDW SHADE ROLLER Henry Znamirowslri, Ellicott City, Md., assigrior to Eastern Products Corporation, Baltimore, Md., a corporation of Maryland Filed Dec. 7, 1961, Ser. No. 157,643 3 Claims. (Cl. 1613-300) The present invention relates to Window shade rollers and more particularly to cord-operated window shade rollers.

Cord-operated window shade rollers are constructed to raise or lower a -window shade upon pulling one or the other side of an operating cord. The operating cord, which may be endless, passes around a cord wheel and rotates the latter, in turn rotating the window shade roller. The action of the cord on the cord Wheel is similar to that in the usual drapery traverse rod. In the case of a traverse rod, the pull required to overcome the resistance due to gravity for opening will be the same as the pull required to overcome the resistance due to gravity for closing, because the weight of the drapery will have an equal effect in each case. However, in the case of a window shade roller, the weight of the window shade will assist in effecting lowering of the shade and will have to be overcome in raising the shade. Moreover, in order to retain the shade in a pantially lowered position, it is necessary to provide means to resist the downward pull caused by the weight of that portion of the shade which is extending downward-ly from the roller.

ln the case of large or heavy shades, and especially of shades made of woven material using metal slats for the weft, it is desirable that the force required to raise or lower the shade be no greater than necessary, and it is desirable that the force required to raise the shade be substantially equal to the force required to lower the shade.

A principal object of the invention has been to provide a novel and improved cord-operated window shade roller mechanism.

More particularly, it has been an object of the invention to provide such a mechanism which is simple and reliable in construction and which permits the shade to be left in any desired partially drawn position.

A further object of the invention has been the provision of such a mechanism in which the force required to raise the shade is substantially equal to the force required to lower the shade.

`Other and further objects, features and advantages of the invention will appear more fully from the following description of the invention taken in connection with the appended drawings, in which:

FIG. 1 is an exploded perspective view illustrating a Window shade roller mechanism embodying the invention;

FIG. 2 is a longitudinal vertical sectional view showing the mechanism of FIG. l assembled;

FIG. 3 is a cross-sectional View taken along the line 3--3 of FIG. 2; and

FIG. 4 .is a diagrammatic view illustrating the operation of the mechanism of FIGS. 1 3.

Referring now to the drawings, and more particularly -to FIG. 1, reference numeral 1G' designates the upper right corner of a window frame to which an L-shaped bracket 11 is attached by screws |12. The outwardly extending leg of bracket 11 has L-shaped tabs `13 and 14 and an L-shaped shelf y15y struck from the surface thereof.

A support fitting ,16 has outwardly extending L-shaped flanges 17 and 18 at respective sides thereof, the flanges "ice 17 and 18 being adapted to be accommodated in the slots formed by the tabs 13 and 14, respectively, and to rest on the shelf 15 to attach fitting 16 to bracket 11. The fitting 16 is provided with a forwardly extending annular flange 19` forming a collar about a circular hole 20. The bottom of iitting 16 is formed into a pair of cord guides 21 and 22.

As shown in FIG. 2, the itting 16 has an axially extending annular ange 23 on the opposite side from flange 19 and forming -with the ilange -19 a bushing for a shaft 24. A locking ring 25 ts over the end of shaft 24 protruding beyond the end of flange 23 and serves to retain the shaft in the bushing.

A ratchet wheel 2'6 is mounted on shaft 24 and may be integral therewith. One` side of ratchet wheel 26 abuts against flange 19. A square collar 27 is mounted on shaft 24 on the side opposite flange 19. `Collar 27 may be integral with shaft 24 and ratchet 26. Ratchet 26 may have any desired number of teeth, but four have been found satisfactory for most purposes.

A pawl 23 having a hook at one end thereof is pivotally mounted on one face of fitting 16 above ratchet 26 so that the hook end of pawl 28 is adapted to engage the ratchet teeth. A pin acting -in a hole in :fitting `16 supports pawl 28 so that the weight of the pawl 28 urges it to rotate in a counterclockwise direction (FIG. l) into engagement with the ratchet teeth. Contact between a tooth of ratchet 26 and the hook end of pawl 23 prevents ratchet 26 from rotating in a counterclockwise direction (FIG. l), and hence also prevents shaft 24 and collar 27 from rotating in a counterclock- 'wise direction. However, the hook end of pawl 28 slides over the ratchet teeth when ratchet 26l rotates in a clockwise direction so that the pawl does not inhibit clockwise rotation of shaft 24 and collar 27.

A cord wheel 29 is mounted on shaft 24 with an elongated hub '30' of cord =wheel 29 being rotatable on the shaft 24. Cord wheel 29 has an annular web 31 joined to hub 30 by spider arms 32 and '33 (FIG. 3). The radially outer end of web 31 is U-shaped in cross section to form an annular open-ended cord. receiving slot 34 in which an operating cord 35 may be received. The walls of slot 34 may be ribbed, as shown at 36 in FIG. l, to provide good traction contact between the Iwalls of cord wheel slot 34 and cord 35.

Web 31 has an axial collar portion 31A which fits into the open end of a hollow shade roller 37, which may be made of metal and which has an axially extending recess 38 at one side which accommodates a block of wood or like material 39 to which the end of a Window shade or the like (not shown) may be attached, as by stapling. The recess 38 may be formed by axially extending folds or bends in the wall of roller 37 at one side thereof. An axially extending block 40 of Wood, metal or the like is aiiixed to the inner periphery of roller 37 diammetrically opposite recess 38.

Collar 31A is provided with elongated slots 41 and 42 adapted to accommodate recess 38 and block 40, respectively. Contact between collar 31A land the Walls of recess 33 and block 40 insures that rotational motion imparted to cord wheel 29 by cord 35 is directly transmitted to roller 37 so that the roller 37 and cord wheel 29 rotate as a unit. The Iaxial length of collar 31A will usually be only a small fraction of the roller length, but the contact afforded between the outer surface of collar 31A and the inner surface of roller 37 :and between the openings in collar 31A and the walls `of recess 38 and block 40 prevents relative rotational slippage between the cord wheel and roller.

A friction Washer 43 is mounted on hub 30 on the side thereof opposite from collar 31A. Friction washer 43 lies against the side of web 31 and is held in contact with the latter by a bowed annular spring washer 44. Washer 44 has a square-sided central opening 45 which fits over and in contact with collar 27 so that washer 44 is caused to rotate with shaft 24.

A retaining washer 46 is mounted on the inner end of shaft 24 to hold shaft l24 in a fixed axial position relative to hub 30. The end of the shaft 24 is staked at four points to hold the washer 46 in place. The shaft 24 may, if desired, be hollow, in which case the end of the shaft may be flared to retain the washer 46.

In the arrangement shown, the window shade will be raised when leg 47 of operating cord 35 (shown in the diagrammatic illustration of FIG. 4) is pulled downwardly to rotate cord wheel 29 in a clockwise direction. Clockwise (FIG. 4) rotation of cord wheel 29 will cause washers 43 and 44, shaft 24 and ratchet 26 likewise to rotate in a clockwise direction. This direction of rotation does not cause pawl 28 to lock with ratchet 26. Hence, for -a raising of the shade the only force required is that needed to overcome the Weight of the shade.

To lower the shade, the opposite cord leg 43 is pulled downwardly, causing cord wheel 29 to rotate in a counterclockwise direction (FIG. `4). However, locking engagement between pawl 28 and ratchet 26 prevents ratchet 26 from rotating and hence also prevents shaft 24 yand spring Washer 44 from rotating. Thus, the force exerted on the cor-d leg 48 (aided by the weight of the `downwardly extending portion of the shade) must overcome the frictiona-l resistance afforded by friction washer 43. The friction washer 43 rotates with cord wheel 29, but, since spring washer 44 is restrained from rot-ating, :a substantial friction-al resistance must be overcome to permit the relative rotation between cord wheel 29 and spring Washer 44. Some slippage may occur between the friction Washer 43 and the adjacent surface of webV 31 of cord Wheel 29, but such slippage will not alter the overall frictional resistance which must be overcome to lower the shade.

When the shade is stopped in `a partially open position, the weight of the shade hanging downwardly from the roller will tend to unwind the remaining portion of the shade by rotating roller 37 and cord wheel 29 counterclockwise (FIG. 4). However, the roller is prevented from rotating by engagement of pawl 2S with :a tooth of ratchet 26. This engagement causes the frictional resistanceof friction washer 43 to oppose rotation of roller 37, thus preventing the shade from being unrolled by its own weight.

Since pawl 28 engages ratchet 26 only for a downward shade motion, the frictional drag :afforded by friction washer 43 must be overcome only for downward shade motion. Hence, the only lforce required on `the operating cord to raise the shade `is that determined by the weight of the shade hanging :from the roller, while the force required to lower the shade is that determined by the resistance ofthe friction clutch comprising Washer 43 less the weight of the shade hanging from the roller. The amount of the frictional resistance afforded by the friction clutch may be selected by appropriate selection yof the spring force exerted byspring washer 44 on friction washer 43.

While the invention has been described in connection with a specific embodiment thereof and in a specific use, various modifications thereof will occur to those skilled in the art Without ydeparting from the spirit and scope of the invention as set forth in the appended claims.

What is claimcdis: p

l. In .a cord-operated window shade roller, `an operating mechanism comprising a shaft, lan annular cord wheel rotatably mounted on said shaft adjacent one end of said shaft and adapted to be aiiixed to one end of said roller for rotation therewith 'as la unit under the action of an operating cord engaged by said cord wheel, a fitting adapted to be supported from a window frame or the like and having :an aperture aligned with 'and forming :a bearing ysurface for the other end of said shaft, `a ratchet affixed to said shaft, a pawl pivotally yattached to said fitting `and having a hook formation arranged to contact said ratchet and to lock said ratchet against rotation in one direction corresponding to :shade lowering rotation of said cord wheel, a friction washer rotatably mounted on said shaft and arranged to contact said cord wheel, a spring washer affixed to said shaft and arranged to contact said friction washer vand to bias said friction washer into friction contact with said cord wheel, said friction washer `and said spring washer forming a friction clutch intercoupling said cord wheel and said shaft whereby rotation of said cord wheel in a shade lifting direction produces a corresponding rotation of said shaft and rotation of said cord wheel in a shade lowering direction is opposed by the frictional resistance of said friction clutch.

2. A cord-operated window shade roller, comprising a hollow roller upon which a window shade or the like is adapted to be lwound, an annular cord wheel mounted at one end of said roller and being coaxial therewith, said cord wheel having an annular projection at one side thereof extending into the end of said roller, cooperating means on said roller and said projection for retaining said cord wheel fand said roller in assembled relationship Iand -for causing said cord wheel and said roller to v rotate together as a unit under the action of an operaing cord engaged by said cord wheel, said cord Wheel having a central annular collar Iaxially aligned with said roller and having an internal surface forming an axially extending bearing surface, a mounting fitting comprising a plate having a circular aperture axially aligned with said collar and said roller, a shaft axially Ialigned lwith and rotatably journaled in said bearing surface and said aperture, a ratchet whee-l affixed to said shaft, a friction Washer mounted on said shaft and arranged t0 `be in contact with said cord wheel, said friction washer being rotatable relative to said shaft, a spring washer mounted'on and lfixed to said shaft for rotation there- -with and arranged to exert a substantial force against said friction washer biasing the latter into contact with said cord wheel, and a pawl pivot-ally mounted on said plate and having a hook formation arranged to contact said ratchet Wheel and to llock said ratchet wheel against rotation in one direction corresponding to shade lowering rotation of said roller but not in the other direction corresponding to shade lifting rotation of said roller, locking of said ratchet wheel preventing rotation of said shaft and said spring -washer as said cord wheel is rotated in a shade lowering direction whereby rotation of said cord wheel in a shade lowering direction is opposed by frictional contact between said friction Washer `and said spring washer and between said friction Washer and Said cord Wheel.

3. A cord-operated Window shade roller, comprising a hollow roller upon which a window shade or the like is adapted to be wound, an annular cord Iwheel mounted at one end of said roller Iand being coaxial therewith, said cor-d wheel having an annular projection at one side thereof extending into the end of said roller, cooperating means on said roller and said projection for retaining said cord wheel and said roller in assembled relationship and for causing said cord Wheel and said roller to rotate together as a unit under the action of an operating cord engaged by said cord wheel, said cord wheel having a central annular collar axially .aligned with said roller and having an internal surface forming an ,axially extending bearing surface, a mounting fitting comprising a plate having a circular aperture axially aligned with said collar and said roller, a shaft axially yaligned with and r0- tatably journaled in said bearing surface and said aperture, la ratchet wheel fixed to said shaft between sai-d fitting .and said cord wheel, a friction Washer mounted on said shaft and arranged to be in contact with said cord Wheel, said friction washer being rotatable relative to said shaft, an arcuate spring washer mounted on and fixed to said shaft for rotation therewith and arranged to exert a substantial force lagainst said friction washer biasing the latter into contact with said cord wheel, ,a pawl pivotally mounted on said plate and having a hook formation arranged to contact said ratchet wheel and to lock said ratchet wheel against rotation in one direction corresponding to shade lowering rotation of said roller :but not in the other direction corresponding to shade lifting rotation of said roller, locking of said ratchet wheel preventing rotation of said shaft and said spring washer as said cord wheel is rotated in a shade lowering direction whereby rotation of said cord wheel in a shade 'lowering direction is opposed by frictional contact between said References Cited in the file of this patent UNITED STATES PATENTS 220,787 Barrett etal Oct. 21, 1879 1,507,324 Nevatt Sept. 2, 1924 1,570,573 Nevatt Jan. 19, 1926

Claims

1. IN A CORD-OPERATED WINDOW SHADE ROLLER, AN OPERATING MECHANISM COMPRISING A SHAFT, AN ANNULAR CORD WHEEL ROTATABLY MOUNTED ON SAID SHAFT ADJACENT ONE END OF SAID SHAFT AND ADAPTED TO BE AFFIXED TO ONE END OF SAID ROLLER FOR ROTATION THEREWITH AS A UNIT UNDER THE ACTION OF AN OPERATING CORD ENGAGED BY SAID CORD WHEEL, A FITTING ADAPTED TO BE SUPPORTED FROM A WINDOW FRAME OR THE LIKE AND HAVING AN APERTURE ALIGNED WITH AND FORMING A BEARING SURFACE FOR THE OTHER END OF SAID SHAFT, A RATCHET AFFIXED TO SAID SHAFT, A PAWL PIVOTALLY ATTACHED TO SAID FITTING AND HAVING A HOOK FORMATION ARRANGED TO CONTACT SAID RATCHET AND TO LOCK SAID RATCHET AGAINST ROTATION IN ONE DIRECTION CORRESPONDING TO SHADE LOWERING ROTATION OF SAID CORD WHEEL, A FRICTION WASHER ROTATABLY MOUNTED ON SAID SHAFT AND ARRANGED TO CONTACT SAID CORD WHEEL, A SPRING WASHER AFFIXED TO SAID SHAFT AND ARRANGED TO CONTACT SAID FRICTION WASHER AND TO BIAS SAID FRICTION WASHER INTO FRICTION CONTACT WITH SAID CORD WHEEL, SAID FRICTION WASHER AND SAID SPRING WASHER FORMING A FRICTION CLUTCH INTERCOUPLING SAID CORD WHEEL AND SAID SHAFT WHEREBY ROTATION OF SAID CORD WHEEL IN A SHADE LIFTING DIRECTION PRODUCES A CORRESPONDING ROTATION OF SAID SHAFT AND ROTATION OF SAID CORD WHEEL IN A SHADE LOWERING DIRECTION IS OPPOSED BY THE FRICTIONAL RESISTANCE OF SAID FRICTION CLUTCH.