US3456710A - Adjustable window shade - Google Patents

Description

July 22, 1969 G. ABRAHAM ADJUSTABLE WINDOW SHADE 2 Sheets-Sheet 1 Filed Sept. 5, 1967 INVFJN'IOK GARNETT AB'RA my Q July 22, 1969 G. ABRAHAM ADJUSTABLE WINDOW SHADE 2 Sheets-Sheet 2 Filed Sept. 5, 1967 INVICN'IOH. GARNETT ABRAHAM United States Patent 3,456,710 ADJUSTABLE WINDOW SHADE Garnett Abraham, 215 Manor Road,

Staten Island, NY. 10314 Filed Sept. 5, 1967, Ser. No. 665,371 Int. Cl. E06b 9/209 US. Cl. 160-298 Claims ABSTRACT OF THE DISCLOSURE A shade for use in covering a window and the like by dispensing a fabric body from a horizontally-positioned roller wherein the axis of rotation of the roller is slightly offset from its true mechanical axis. The shade also includes a drag wheel coupled to its recoil spring for imparting a frictional drag on the roller of the shade during its movement so that the shade may assume a stable position for any height setting during its operation.

This invention relates to a self-adjusting window shade.

More specifically, this invention relates to a shade having a fabric body for covering a window which may be raised and lowered to any desired height by means of a counter-balanced arrangement which does not utilize ratchets or stops.

In conventional window shades which dispense a fabric body from a roller mounted horizontally at the top of the window frame, it is customary to employ a spring and catch mechanism housed within the roller to permit adjustment of the fabric body to any position. The catch mechanism of the conventional window shade which serves as a lock for its coil spring has the disadvantage of frequently not releasing the shade to permit easy adjustment of the fabric body. The catch mechanism also undergoes excessive wear after repeated use and becomes unreliable in holding the fabric body of the shade to the desired height. The catch mechanism sometimes releases suddenly thus causing the fabric body of the shade to rapidly wind itself up around the roller, damaging the fabric of the shade.

Accordingly, the present invention provides a shade which includes a fabric body dispensed from a roller which is counter-balanced to permit adjustment of the fabric body for any height. The shade, according to the invention, utilizes no catch or lock mechanism which may be subject to wear and provides a smooth and reliable operation during adjustment of the fabric.

The axis of the shade according to the invention has been slightly offset from the central axis of the roller in order to provide a plurality of stable positions to counteract the tension of its coil spring and permit it to be adjusted over a wide range of heights. Moreover, a damping, or drag member, is provided within the body of the roller which counteracts small movements of the roller with respect to the window frame to provide additional stability to the fabric body during its adjustment. The collective effect of these features working in combination provides a freely adjustable window shade which overcomes many of the disadvantages of conventional shades requiring catch mechanisms.

Therefore, it is an object according to the present invention to provide a shade mechanism which is self-balancing for any position of the fabric body of the shade.

It is another object according to the present invention to provide a self-balancing window shade which overcomes the inherent disadvantages of conventional shades.

It is still a further object according to the present invention to provide a shade mechanism which is simple in design, eays to manufacture and reliable in operation.

Other objects and features of the present invention will become apparent from the following detailed description ice considered in connection with the accompanying drawings which disclose an embodiment of the invention. It should be understood, however, that the drawings are designed for the purpose of illustration only and not as a definition of the limits of the invention as to which reference should be made to the appended claims.

In the drawings wherein similar reference characters denote similar elements throughout the several views:

FIG. 1 illustrates the position of the window shades secured within a conventional window frame;

FIG. 2 is a cross-sectional view through section 2-2 of the roller of the window shade of FIG. 1;

FIG. 3 is a cross-sectional view through section 3-3 of the roller of the window shade of FIG. 1;

FIG. 4 is an end view of the roller of the window shade taken through section 44 of FIG. 2;

FIG. 5 is an end view of the opposite end of the roller of the window shade taken through section 5-5 of FIG. 3;

FIGS. 6 and 6a are a cross-sectional view through the mechanism of the roller taken along section 6-6 of FIG. 2 for two positions of the roller; and

FIGS. 7 and 7a are a cross-sectional view taken through the mechanism of the roller along section 77 of FIG. 2, showing it in two positions.

Referring to FIG. 1, there is shown the window shade according to the invention having a fabric body 11 which is adjustable in height from roller 12 secured between the inside supports adjacent to the top edge of window frame 10.

FIG. 2 shows a cross-sectional view taken through roller 12 of one end of the window shade according to the invention having a flat or key pin 15 engaged in a corresponding slot in fastener 14. Fastener 14 is secured to the inside wall surface of window frame 10 by means of tacks 18. Key member 15 is pivotably seated within recess 26 of cylindrical end block 13 and secured at its opposite end to shaft 20 which extends a distance along the inside of roller 12. Surrounding shaft 20 and extending along most of its length is a helical coil spring 19. The free end 30 of spring 19, adjacent to key member 15, is secured to cylindrical end block 13. The opposite end 31 of spring 19 is secured to shaft 20 as shown in detail in FIGS. 7 and 7a. With cylindrical end block 13 secured to the inner walls of roller 12, any rotation of roller 12 with respect to key pin 15 will cause spring 19 to wind or unwind around shaft 20.

Secured to the extending end of shaft 20 within roller 12 is a cylindrical drag wheel 21. Drag wheel 21 has an external diameter slightly smaller than the internal diameter of roller 12 so that its circumferential area in contact with the internal walls of roller 12, will cause a frictional restraining drag as roller 12 rotates with respect to key pin 15.

Referring to FIG. 3 there is shown a detailed cross-sectional view of the opposite end of roller 12. Secured at the end of roller 12 is a cylindrical end block 22 for having axle pin 23 mounted therein. Axle pin 23 includes a flange 25 for positioning against the exposed surface of block 22. Pin 23 is inserted into aperture 24 of fastener 126, secured in a similar manner with respect to fastener 14 to window frame surface 10.

Axle pin 23 and key pin 15 are secured to their respective end plates 22 and 13 along a common axis denoted by line 16 which is offset a small distance from the original geometrical axis 17 of roller 12 as illustrated in detail in FIGS. 4 and 5. The effect of this offset is to cause a raising and lowering of the center of gravity of roller 12 as it rotates with respect to pins 15 and 23.

The shade according to the invention operates as follows:

Initially, the shade is inserted between fasteners 14 and 126 with a small tension applied to coil spring 19. The tension is applied to the spring by twisting the shade with respect to key pin until spring 19 has the ability to. maintain fabric 11 in a stable position when the shade is almost completely rolled up. As the fabric of the shade is pulled downward, the tension in spring 19 increases to counteract the additional weight of the fabric exposed below roller 12. The downward movement of the fabric also causes roller 12 to rotate, producing at raising and lowering of its center of gravity. When the center of gravity of roller 12, as denoted by line 17, is at its lowest position, such as shown in FIGS. 6 and 7, the fabric of the shade may then assume a stable height position. When the center of gravity of roller 12 moves to its uppermost position, roller 12 will have a tendency to rotate in either direction 180 to its most stable position at its lowest center of gravity. However, drag wheel 21 which is the frictional contact with the internal walls of roller 12 prevents roller 12 from rotating to its more stable position and thus maintains the height level of the fabric for any setting of the shade. Due to the eccentric motion of roller 12 with respect to its common rotational axis 16, it can be appreciated that the force exerted by drag wheel 21 against the lower internal surface of roller 12 is greatest when the center of gravity 17 is moved in the vicinity of its uppermost position. Likewise, drag wheel 21 exerts the least amount of frictional drag force against the internal cylindrical surface of roller 12 when its center of gravity 17 moves to its lowest and most stable position. The combined effect of drag wheel 21 and the offset center of gravity is to provide a shade which will assume a stable position for any height adjustment of its fabric body. When raising the shade to its most open position the momentum of roller 12 will wind its fabric body up until the end of the fabric reaches the roller. The balancing effect produced by the offset and the drag wheel prevent the shade from running away with itself at the top of the roller as is common with conventional shades.

In an actual embodiment of the shade having an offset between centers 16 and 17 of &2", the outer diameter of roller 12 was 1%" and the diameter of the drag wheel was approximately 1 /2". Spring 19 was /2" diameter having the length of approximately 8", typical of those found in conventional window shades. The inner diameter of roller 12 was made slightly larger than the outer diameter of drag wheel 21 in order to permit frictional contact during the movement of the roller. The frictional surface along the circumference of drag wheel 21 may be lined with felt or other fabric which would enhance its frictional retaining properties during the movement of the shade.

While only a single embodiment of the invention has been shown and described, it will be understood that many changes and modifications may be made there unto without departing from the spirit and scope of the invention as defined by the appended claims.

What is claimed is:

1. An adjustable fixture for dispensing a fabric body from a cylindrical roller for covering windows and the like comprising:

pivotable means for supporting the cylindrical roller on an axis slightly offset from its geometrical :lXlS,

a helical coil spring coupled between said pivotable means and the cylindrical roller to counterbalance the weight of the fabric body dispensed from the roller, and

drag means coupled to said pivotable means for imparting a frictional drag on the cylindrical roller during rotational movement of the fixture.

2. The shade as recited in claim 1 wherein said pivotable means comprises an axle pin secured to each end of the cylindrical roller, each pin being eccentrically displaced in the same direction by the same amount along an axis slightly offset from the geometric axis of the cylindrical roller.

3. The shade as recited in claim 2 wherein one of said axle pins is keyed and restrained from movement with respect to the movement of said roller; said keyed pin being coupled to said spring.

4. The shade as recited in claim 3 wherein said drag means comprises a wheel connected to the extension of said keyed axis and having a diameter sufiicient for fractional engagement with the internal walls of said roller.

5. The shade as recited in claim 4 wherein said drag wheel includes a friction bearing surface deposited on its circumference in contact with said roller.

References Cited UNITED STATES PATENTS 225,582 3/1880 Fisher et al 291 283,737 8/1883 Shaw 160299 824,930 7/1906 Hopkins 16029l X 1,975,633 10/1934 Cakora 160-303 X PETER M. CAUN, Primary Examiner

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