US1941383A - Operating mechanism for curtains, shades, or the like - Google Patents

Description

M. B. BENSON Dec. 26, 1933.

OPERATING MECHANISM FOR CURTAINS, SHADES, OR THE LIKE Filed Feb. 26, .1932

INVENTOR.

Mink/J1. 601160114 L4; nib? h ATTORNEYS.

Patented Dec". 26, 1933 UNITED STATES OPERATING MECHANISM FOR CURTAINS,

SHADES, OR THE LIKE Melvin B. Benson, New York, N. Y., assignor to Shredwood Curtain 00., Worcester, Mass., 8. firm composed of Alfred S. Moses and Fred A.

Walker, trustees Application February 26, 1932. Serial No. 595,256

6 Claims.

The present invention relates to an improved operating mechanism particularly suitable for window or porch shades and comprising a novel device which permits ready adjustment of the length of a roll type shade, has but few moving parts and is simple and economical to manufacture.

Roll type shades for windows or porches are ordinarily provided with pairs of cords by means of which a shade is raised or lowered. These cords must be securely fastened to prevent accidental unrolling of the shade. To permit of easy and rapid adjustment of the shade, release of the cords should require but a minimum of effort and l the cords should be prevented from twisting.

The device of the present invention is so constructed that the operating cords are securely held against slippage when the shade is in any desired position and are released for operation of the shade by a simple manual lateral movement; the cord being held properly alined at all times. An important feature of the invention is the simplicity of the mechanism and the parts thereof.

The preferred embodiment of the novel operating mechanism is illustrated in the accompanying drawing of which:

Fig. 1 is a perspective view of a shade provided with an operating mechanism constructed according to the invention;

Fig. 2 is an enlarged front view of the operating mechanism of Fig. 1, shown in cord locking position;

Fig. 3 is a side view of the mechanism; and

Fig. 4 is a fragmentary view, partly broken away, showing the cord gripping members of the mechanism in cord releasing position.

Referring to the drawing, a roll type shade 1 operable by cords 2 and 2 is illustrated in Figs. 1 and 2. One end of cord 2 is secured in the rear of shade 1 adjacent a guide pulley 3; the cord extending vertically down on the rear side of the shade, passing around the bottom edge of the shade, up to and around pulley 3 and then horizontally to a guide pulley 4. Similarly cord 2' is secured in the rear of shade 1 adjacent a guide pulley 3, extends vertically down the rear of the shade, passes around the lower edge thereof and up to and around pulley 3' from which pulley it extends horizontally along with cord 2 to pulley window frame and a front member 8 generally triangular in shape, which is parallel to the fastening member '7 and sufficiently distant from the wall to overhang the top of the shade. On the upper corner of member 8 is a shaft 10 upon which is rotatably mounted the guide pulley 4 for cords 2 and 2'. Similar shafts 12 and 14 are secured to each of the other corners of member 8. Rotatably mounted on shaft 12 is a segmental gear 16 which meshes with a similar segmental gear 18 mounted on shaft 14. Integral with or rigidly attached to gear 16 and shown best in Fig. 4 is a gripping surface 20 which, in the embodiment of the invention illustrated, comprises a plurality of teeth 21 disposed about an arcuate surface eccentric to shaft 12. A similar gripping member 22 comprising teeth 23 disposed about an arcuate surface eccentric to shaft 14 is formed integral with or is attached to gear 18. Members 20 and 22 are positioned rearwardly with respect to gears 16 and 18 as indicated by the dotted lines in Fig. 2 and adjacent the surface of plate memher. 8 so as to be in the plane of pulley 4.

As shown best in Fig. 4, the radii of curvature of the gripping surfaces of members 20 and 22 are so chosen that the greatest separation between the two members occurs when gears 16 and 18 are rotated into position where their uppermost portions are in mesh; members 20 and 22 being brought into close proximity when the lowermost portions of gears 16 and 18 are in mesh at which time the gripping surfaces are substantially in line with a tangent to the peripheryof pulley 4.

An operating arm 24, formed integral with or attached to the arm carrying gear 18 extends vertically downward from shaft 14 when the lower portions of gears 16 and 18 are in mesh as shown in Figs. 1 and 2, and terminates in a horizontal portion 26 provided at its extremity with apertures 28. Cords 2 and 2' after passage about guide pulley 4 pass between members 20 and 22 in the rear of gears 16 and 18 and through ap-' ertures 28 in the horizontal portion 26 of arm 24..

With the mechanism in the position illustrated in Figs. 1 and 2, cords 2 and 2 are firmly'secured between members 20 and 22 and consequently movement of the shade is prevented.

To release the cords for adjustment of the shade it is only necessary to rock arm 24 into the 10 position shown in Fig. 4 which may be effected by simply pulling the lower ends of cords 2 and 2' to the left. Such a lateral movement of the cords serves through arm24 to rock gears 16 and 18 and the gripping members integral therewith 110 about the respective shafts 12 and 14 and to thereby cause relative separation of the gripping teeth 21 and 23 with consequent release of cords 2 and 2'. If the shade is to be lowered, release of the cords is all that is necessary; gravity serving to cause unrolling of the shade. If the shade is to be raised, cords 2 and 2' are pulled downwardly and to the left until the desired position of the shade has been reached. The cords are then moved laterally to the right until arm 24 is vertical, the parts being thusretumed to the locking position illustrated in Figs. 1 and 2.

With the mechanism above described, inadvertent return to unlocking position is prevented as cords 2 and 2' are always under tension due to the effect of the weight of the shade, and this tension, being upward at the point of, contact with the gripping surfaces 20 and 22, tends to bias the device toward locking position. The weight of arm 24, being suspended in line with the axis of shaft 14, is removed from the gear segment and gripper, and this arm tends to assume a vertical position for automatically locking the cord. As the gripping surfaces are so shaped that there is a different degree of separation therebetween for each position ofthe gears, the device will operate with cords of different sizes, the cords being kept properly alined at all times. As there are but two moving parts there is nothing to get out of order and the device is extremely simple to manufacture and to install. j

The preferred embodiment of the invention has now been described in connection with its utility a frame member, a pulley carried by said frame in releasably securing the pair of operating cords of a roll type shade. Obviously whether one, two or several cords are to be secured is immaterial as is also the particular construction of shade or points thereof, a separate guide pulley for each of said cords and a unitary cord securing and adjusting mechanism including a plate member, a pulley mounted thereon for guiding both of said cords, a pair of shafts mounted on said plate member parallel with the axis of rotation of said last mentioned pulley, a gear rotatable on one of said shafts and carrying therewith an eccentric gripping member and an operating arm, a second gear in mesh with said first gear and rotatable on the other one of said shafts and likewise carrying an eccentric gripping member, said gripping members being positioned at opposite sides of said cords and between said plate and said gears and being so shaped that rotation of said gears in the direction of movement of said cords toward said last mentioned pulley brings said surfaces into engagement with the cords to secure the shade in position and rotation of said gears in the opposite direction releases the cords to permit adjustment of the shade.

2. A unitary mechanism for adjustably securing the cords of curtains and'the like comprising member, a pair of segmental meshing gears pivoted to said frame member, a pair of cam-shaped gripping members carried respectively by the gears and with their gripping surfaces offset from the pulley axis and approximately in line with a tangent to the pulley periphery, said cam shaped gripping members being adapted to grip the cord when moved upwardly and an operating arm suspended from the axis of one of said gears so as to remove the weight thereof from said gear and to automatically cause said gripping members to grip said cord when the suspended arm is released.

3. The combination according to claim 2 wherein the operating arm fastened to one of said gears depends vertically downward from the associated shaft and is provided with an aperture at the end thereof remote from said gear for the passage therethrough of the cords, v said arm being vertically disposed when the gripping surfaces are in cord engaging position whereby lateral movement of the ends of the cords rocks said arm and causes rotation of said gears in a direction to release the cords and the relative weight of said arm tends to restore the parts to gripping position by gravity.

4. In a device of the character set forth, a bracket comprising a fastening member and a plate member, a pulley carried by said plate, a pair of segmental meshing gears pivoted to said plate, a pair of cam shaped gripping members carried respectively by the gears in the plane of the pulley and between the gear and the plate and with their gripping surfaces offset from the pulley axis and approximately in line with a tangent to the pulley periphery, and an operating arm attached to one of said gears and having means for engaging a cord passing over the pulley, between the gripping devices.

5. A mechanism of the type described for releasably securing a cord for shades and the like comprising in combination a pair of movable segmental members each provided with a gripping surface disposed at opposite sides of the cord and adapted in one position to engage and hold the cord therebetween against upward longitudinal movement and a pair of meshing segmental gears each movable with one of said members for moving the same into and out of cord engaging and disengaging position including an operating arm whic is secured to one of said gears and is provided with an aperture for passage of the cord therethrough whereby rotation of said gears may be effected by lateral movement of the cord, said operating arm being suspended from the axis of rotation of one of said segmental gears to tend by gravity to cause the parts to assume cord securing position.

6. In combination with a cord or the like, biasing means tending to move said cord in the forward direction, mechanism for releasably securing the cord against movement by said means, said mechanism including a pair of movable members each provided with a gripping surface disposed at opposite sides of said cord and adapted in one position to engage andhold the cord therebetween, and a pair of meshing segmental gears each integral with one of said members for moving said members into and out of cord engaging position, the gripping surfaces of said members being so formed that rotation of the gears in the direction toward which the cord is biased by said means brings said surfaces into cord engaging position, and a weighted operating arm suspended from the axis of one of said gears and automatically causing said gripping members to grip the cord.

MELVIN B. BENSON.

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