US2165492A - Venetian blind actuating mechanism - Google Patents

Description

. J y 11, 1939. H. K. LORE'NTZEN' 2.165.492

I VENETIAN BLIND AGTUATING IIECIiANISI Filed Jan. 5, 1937 llll-lllllll nun-nun INVENTOR. flaw/K lam/22%? M ATTORNEYS Patented July 11, 1939 UNITED sTATEs PATENT or-l-lca Claims.

, This invention relates to hardware to be incorporated in Venetian blinds; and at present the invention finds its principal use in actuating mechanism for changing the inclination of t the 5 slats of the blinds. Originally much of the subject-matter of this application was presented in my prior application Serial No. 14,557 filed April 4, 1935, on which Patent 2,075,211 issued on March 30, 1937, and of which prior application this isa continuation in part.

' In many Venetian blind installations the inclination of the slats is varied by a worm gear or other tilting mechanism which is actuated by a pull cord that passes around a driving pulley.

.1 Usually the tilting mechanism is located at the top of the window, at one side; and the operating cord is looped over the driving pulley with the ends of the cord hanging down far enough to be conveniently grasped by a person wishing to operate the tilting mechanism. For the sake of conforming to appearances and space re-, quirements the driving pulley is usually made quite small, with the result that there. is a tendency for the cord to slip on the pulley. Means have heretofore been proposed for preventing such slippage, but in general, some slip: page takes place from time to time in actual practice. This slippage is not suflicient to interfere with the tilting operation, but is objectionable because it is usually more pronounced in one direction than in the other. The result is that over a period of time the slippage causes one end of the cord to move higher and higher, so that the cord has to be periodically repositioned on the pulley.

An object of the present invention is to provide a cord-and-pulley actuated tilting mechanism which can be so manufactured on a commercial" basis as to minimize slipping of the cord.

Another object of the invention is to provide a cord-'and-pulley actuated tilting mechanism which renders unobjectionable gradual advance of the cord around the pulley in one direction or the other. A further object of the invention is to provide tilting mechanism for Venetian blinds which can be economically and satisfactorily fabricated, largely from stamped sheet metal, on a quantity production basis.

A still further object of the invention is to provide a Venetian blind tilter which will be attractive in appearance and rugged and reliablev in service.

Various specific objects of the invention will be apparent to those skilled in the art fromthe disclosure herein of illustrative preferred embodiments of the invention.

Fig. I of the drawing is a front elevation showing tilting. mechanism of the present invention 5 and fragments of the blind suspension bar and tilt slat.

Fig. II is a section taken approximately on. the line II-II of Fig. I. r

Fig. 111 is a detail view, showing the assembly 10 of two component parts. A portion of the view is in vertical section approximately on line III-III of Fig. I.

Fig. IV is a fragmentary view showing in front elevation a second form of pulley organi- 15 -zation with bead-chain drive.

Fig. V is a fragmentary view showing in front elevation the same structure as Fig. IV but with a; cord drive for the pulley.

Fig. VI is a fragmentary view showing in front 20 elevation a third specific form of pulley organization with cord drive.

Fig. VII is a perspective view of fastening device used for uniting the ends of the pulley v cord.

Fig. VIII is a top plan view showing how the 25 two ends of the pulley cord may be united by a second formof fastening device.

Fig.1 is a fragmentary view showing a portion of the fastening device of Fig. VIII as seen 30 from the line IX-IX in Fig.V1II.

Reference will first be had to Figs. I to III. The tilting mechanism designated as a whole by A is attached by screws B or other suitable means to a suspension bar C, arid serves to support and actuate the upper or tilt slat D of the blind. The tilting mechanism A is assembled about a stamped sheet metal bracket having 'a horizontal leg I and a vertical leg 2. The vertical leg 2 is stamped with a vertical strengthening 40 rib 3 and with a rectangular aperture 4 which accommodates a worm ll. Pivotally attached to the lower end of bracket leg. 2 is a U-shaped sheet metal rocker member 5 having vertical legs 5' and 5 The upper edge of leg 5 is arcuate -'in shape and is formed with teeth which mesh with worm IL' Welded against one side of leg 5' may be a generally semi-circular plate 5'which is also formed with teeth that mesh with the worm H. The arrangement is such 50 that leg 5 and the plate 5' act as a single gear sector, the plate 5' being added to give increased thickness to the teeth. The arm 5 is arranged to receive a suitable coupling member carried by the tilt slat D which coupling mem- 55 ber may comprise two pins 6, 6 which enter holes in the arm I".

Pressed into the vertical bracket leg 2 is a horizontal groove adapted to receive a bushing I which acts as a shaft bearing. This bushing I may be held in place by a sheet metal strap 3 which is looped about the bushing and has its ends passing through rectangular openings in the bracket leg 2, and clinched at 3', I on the opposite side of the bracket leg. Preferably the bushing 'l is. provided'with a circumferential groove 1' in which the clamping strap 3 fits to prevent longitudinal movement of the bushing 'l. Suitably secured adjacent. to the outer end of the bushing I is a sheet metal disc 9 having an outwardly projecting finger 9. The outer end of bushing I may be provided with an annular shoulder as'shown in Fig. 111, and the disc 9 may have a central aperture which is a tight fit on the end of the bushing and rests against the shoulder. At intervals around the outer end of the bushing I, the metal may be upset as at l to secure disc 9 tothe bushing. Adjacent to its periphery the disc 9 may have a radial notch 9" which receives an integral fin (not shown) projecting from the bracket leg 2 when the parts are assembled on the bracket. Assembled in the bushing I is a shaft l having on its'inner end the worm Ill which meshes with the gear sector as shown in Fig. 11.

Pivotally suspended from the stationary finger 9' is an oscillatory cord guide made from a single piece of stamped sheet metal and designated as a whole by I5. The guide l5 has a' disc portion l5 which lies adjacent to' the stationary disc 9 and which has an elongated hole li through which the shaft l0 passes. A V-type driving pulley I6 is positioned adjacent to the disc portion and is fixedly secured to the outer end of the shaft Ill. The guide I5 is formed with portions which are bent outwardly to form guide members 15 which extend circumferentially of the pulley groove. The lower end of the guide I5 is formed with fingers l5 which are brought together as shown in Fig. I to form a loop beneath the pulley. A cord I8 is looped over the pulley and passes, as shown, through the loop of the oscillatory guide. Preferably the cord is an operatively endlessone; such as will be described later.

The pulley l6 may be made from two slightly coned discs of stamped sheet metal l6 and li having radial ribs l9 pressed inwardly to improve the frictional contact between the cord and the pulley. Preferably the radial ribs 16 on one side of the pulley are circumferentially staggered with respect to those on' the other side of the pulley; and this can be efiected with pulley halves that are identicalstampings. For this purpose the outer end of shaft l0 may be square, and the center hole in the pulley stampings may likewise be square. If eight equally spaced radial ribs are pressed in each' pulley half, and 'if the diagonal of the square hole passes 11% degrees from theribs, the assembly of two identical stampings on the squared shaft willlocate the ribs on the two halves of the pulley in staggeredrelation.

' Fig. IV shows a chain drive and a modified oscillatory guide which may be applied to the tilting mechanism of Figs. I and II. The oscillatory guide is designated as a whole by and includes a plate portion 215' which is behind the pulley I6 and is pivoted at 29' to the angle bracket which carries the worm and gear tiltstamping IS' which has no radial ribs.

ing mechanism. Stamped integral with the plate "'5 are guide members 28, 25 which are in circumferential alignment with the pulley;

and from the guide members 25 fingers 25, 25'

'chain is pulled in the directionindicated by the arrow the guide 25 swings to the right as shown in Fig. IV. When the chain is pulled in the opposite direction the guide swings to the left and will move into the same position as is shown in Fig. V.

In Fig. V the structure is the'same as in Fig. IV, except that the flexible pulley' driving ele ment is a cord; and duplicate parts are designated by the same reference characters used in Fig. IV. The pulley I6 is driven by a. braided cord 33. and preferably the ends of the cord are united by a fastening device 39 so as to render the cord operatively endless. The fastening device 39 is.of such character that it can pass between the guide fingers and the pulley and travel around the pulley as the same is rotated. Thus if the cord gradually advances in one direction, due to unequal slippage, no difiiculty is occasioned and no periodic repositioning of th cord on the pulley is required.

Fig. VI illustrates a construction'in which there is a cord guide which does not oscillate. This guide includes a plate portion 35 'which is locatedbehind the pulley l6 and which has a round hole (not shown) that fits over the worm shaft l0. Plate 35 also has a radial notch 35' that receives a stationary metal finger 30, which is integral with the bracket. Integral with the plate portion 35* there is horizontal shelf portion 35' which is pierced to form an elongated hole,

the metal being drawn to provide an integral thimble 35' which gives a greater bearing surface for the operating cord 48. As shown, the cord 48 passes through the hole in the shelf 35, around the pulley, and back through shelf 35. Preferably the ends of the cord are fastened together as shown in Fig. V to render the cord operatively endless. Since the endless cord renders slippage of the cord on the pulley of less importance,- the pulley may be made of a back stamping li which is identical with the stampings shown in Figs. 11 and III and with-afront With this construction the radial ribs on the back pulley stamping are relied upon to minimize slippage of the driving cord; and the plain stamping it in front gives a better appearance.

Fig. VII shows the fastening device 39 before it has been applied to the cord. It is a single arcuate stamped piece of sheet metal having serrated edges 39 and 39 which meet in dove-tail fashion (as shown in Fig. V) when the fastener is clinched about the cord. [At the ends of the fastener there are small teeth 39 (four shown) which are projected radially into the cord and jprevent the ends of the cord from being pulled out of the clinched fastener. It will be understood that the fastener 39 is firmly clinched on the cord. and this is preferably done with a tool which makes a series of circumferential extending line contacts with the outer surface of the fastener. Figs. VIII and 1x show a swivel fastening device which may be used instead of fasteners 39 to unite the two ends of the cords. Unitary sheet metal stampings 49, 49 are each generally similar to the fastener 39 and are provided with several teeth 49 (three shown) which are projected into the cord 38 when the member 49 is clinched on the cord. However, the members 49, 49 are provided with end portions 49, 49 which receive rivet-like connecting members 1', 1*. For the sake of illustration Fig. VIII shows one member 49 clinched on one end of the cord and the other member 49 before the cord end has been inserted into it. The rivet-like connecting members 1', r are joined by a metal ball F which is similar to one of the balls of the bead-chain 28. This construction gives a more flexible union of the two ends of the cord, so that the connecting device passes more readily between the guide member and the pulley. Also since the connection is swivelled no special care need be exercised to have the cord free of twists when the fastener is applied.

An alternative construction is to omit ball F and one of the rivet-like members r;-and connect members 49, 49 by a'single rivet-like member 1'. A similar construction may be made by omitting ball F and both rivet-like members 1', and forming the members 49, 49 with integral hook-like fingers which are linked together and clinched after the manner of two links of a chain.

In compliance with the patent statutes I have shown the best forms in which I have contem-- plated applying my invention, but it will be understood that the disclosure is illustrative of the invention and does not limit the scope of the same.

What is claimed is:

1. A Venetian blind fitting comprising: a horizontal shaft, a pulley mounted on the shaft, a movable guide plate behind the pulley and mounted on a pivot located above the shaft, the

a guide plate having an opening about the shaft to permit lateral movement of the guide plate, and a pair of guide fingers extending from the plate over the periphery of the pulley below the axis of the pulley.

2. A Venetian blind fitting comprising: a horizontal shaft; a pulley mounted on the shaft; a flexible operating member passing around the pulley to rotate the same; a movable guide plate behind the pulley and mounted on a pivot located above the shaft, the guide plate having an opening about the shaft to permit lateral movement of the guide plate; and a pair of guide fingers extending from the plate over the periphery of the pulley below the axis of the pulley, the guide fingers holding the flexible operating member in contact with the pulley throughout a distance in excess of 250 of the pulley circumference.

3. A Venetian blind fitting comprising: a horizontal shaft; a pulley mounted on the shaft; a flexible operating member passing around the pulley to rotate the same; a movable guide plate behind the pulley and mounted on a pivot located above the shaft, the guide plate having an opening about the shaft to permit lateral movement of the guide plate; and a pair of guide fingers extending from the plate and holding the flexible operating member in'contact with the pulley throughout a distance in excess of 250 of the pulley circumference.

4. A Venetian blind fitting comprising: a horizontal shaft; a pulley mounted on the shaft; a flexible operating member passing around the pulley to rotate the same; a movable guide plate behind the pulley and mounted on a pivot located above the shaft,-the guide plate having an opening about the shaft to permit lateral movement of the guide plate; and a pair of guide fingers extending from the plate below the axis of the pulley and formed into a single loop substantially aligned with the central plane of the pulley, both branches of said flexible operating member passing through the loop whereby the loop holds the flexible member in contact with the major portion of the pulley circumference.

5. A Venetian blind fitting comprising: a horizontal shaft; a pulley mounted on the shaft; a flexible operating member passing around the pulley to rotate the same; a movable guide plate behind the pulley and mounted on a pivot located above the shaft, the guide plate having an openingiabout the shaft to permit lateral movement of the guide plate; anda single guide loop extending from the plate below the axis of the pulley and substantially aligned with the central plane of the pulley, both branches of said flexible operating member passing through the loop contact with the major portion of the pulley 5o circumference. I

HANS K. LOREN'IZBN.

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