US2110710A - Venetian blind tilter - Google Patents

Description

March 8, 1938; H, LORENTZEN 2,110,710

VENETIAN BLIND TILTER Original Filed April 4, 1935 INVENTOR Hamfi. Lmwztzem Patented Mar. 8, 1938 UNITED, STATES PATENT OFFICE 14,557. Divided and this application October 15, 1936, Serial No. 105,688

8 Claims.

This invention relates to hardware to be incorporated in Venetian blinds, and more particularly to a mechanism for changing the inclination of the slats of the blind. Originally the subject-matter was presented in myprior application, Serial No. 14,557, filed April 1, 1935 (Patent No. 2,075,214, March 30, 1937), of which application this is a division.

An object of the invention is to-provide tilt- 10 ing mechanism which can be economically and satisfactorily fabricated, largely from stamped sheet metal, on a quantity production basis.

Another object of the invention is to provide a Venetian blind tilter which will be attractive in appearance and rugged and reliable in service.

Various specific objects of the invention will be apparent to those skilled in the art from the disclosure herein of an illustrative preferred embodiment of the invention.

Fig. I is a vertical section through the suspension bar of a Venetian blind, showing in side elevation tilting mechanism of the present invention attached to the suspension bar.

Fig. II is a fragmentary rear elevation showing the tilter attached to the suspension bar and the top slat of the blind attached to the tilter.

Fig. III is a fragmentary horizontal view taken in general on the line III-III of Fig. I, with a fragment of the top slat of the blind added to the structure shown in Fig. I.

Fig. IV is a fragmentary vertical section taken in general on the line IV-'IV of Fig. I, with a fragment of the top slat of the blind added to the structure shown in Fig. I.

Fig. V is a horizontal detail view, partially in section, showing the gear sector and worm illustrated in Fig. I.

Fig. VI is an isometric view showing an end of the top slat of the blind, with a modified form 40 of attaching member.

The tilter, or tilting mechanism, is intended to be used with a Venetian blind of well known conventional construction and hence the blind itself is not disclosed herein. The blind may be supported from/the top of a window frame, but ordinarily it is supported from a suspension bar I which is fastened adjacent to the top of the window and carries pulleys and cords (not shown) for raising and lowering the blind. At present,

it is the usual practice to place the tilter of Fig. I at the left hand end of the suspension bar (the bar being viewed from within the room) but occasionally, the tilter is placed at the-right hand end of the bar. In the disclosure herein, it

will be assumed that the tilter is placed at the left hand end of the bar I, but if 'it is to be placed at the right hand end of the bar, the construction of the mechanism is the same except that it is made of the opposite hand.

The tilter includes an angle bracket 2 which depends from the suspension bar I and to which is pivoted a U-shaped rocking member 3 that is adapted to have connected to it the top or tilt slat 4 of the blind. Integral with the U-shaped rocking member 3 is a gear sector portion 6 that is operated by a worm I, driven from a pulley 8 and a cord 9. While any suitable form of worm may be used, the worm shown is stamped from a disc of sheet metal. After the worm has been formed, it is riveted to one end of a shaft I0 and the shaft is slipped into a brass bushing II. The pulleyil may be of any suitable form but as shown it is composed of two coned sheet metal discs 8 and 8 After the shaft I0 has been placed in the bushing II, the pulley 8 is suitably secured to the free end of the shaft, as by rivet- The depending leg of the bracket 2 is formed with an opening 2*, for accommodation of the worm 'l', and with a horizontal partly cylindrical portion l3. f The bushing II, with the gear and pulley attached thereto as previously described,

is assembled with the angle bracket 2, the gear 1 extending in the-opening 2 and the bushing ll lying in depression l3. The bushing may be fastened in this position by means of a metal strap l4 which fits into a circumferential groove H formed in the bushing l I, the ends of the strap being passed through slots in the bracket 2 and having their ends bent outwardly against the face of the bracket as shown in Fig. IV.

The U-shaped rocking member 3 is pivoted to the lower end of bracket 2 by means of a brass bearing pin H which is riveted to bracket 2 and which engages only the inner leg of the U-shaped rocking member. The outer leg of the U-shaped rocking member is appropriately formed to receive a coupling member carried. by the top or tilt slat of the Venetian blind; and as shown, this rocking member is formed to receive either of two forms of couplings. In Figs. II, III, and IV, the top or tilt slat 4 of the blind is provided with a pair of coupling pins I8, I 8 which are adapted to be inserted in holes 3, 3 in the rocking member. As shown in Fig. VI, the top or tilt slat 4 of the blind is provided with a stamped metal fitting l9 having a fiat tongue end l9" which may be'inserted into the slot 3'" of-the U-shaped rocking member.

The side of the U-shaped rocking member which lies against the bracket 2 has its upper edge formedsemi-circularly and cut to form gear teeth 6. In order to widen the gear teeth, for purposes that will be explained hereinafter, a semi-circular plate 6' is formed with teeth similar to the teeth 5; and plate 6' is positioned against the portion 6 of he rocking member with the teeth on the two members slightly in echelon as shown in Fig. V. The parts 6 and 6' are permanently secured together in this relationship, preferably by spot welding.

By the use of plate 6, the thickness of the gear teeth is doubled, while permitting the parts to be made from a weight of sheet metal that is easy to cut and stamp. When a stamped sheet.

metal worm is used there is only a slight circumferential overlap of the two ends of the worm thread, and it is helpful to have double thick teeth on the rocking member 3 in order to insure engagement of the worm with one tooth before the worm has disengaged from the preceding tooth. The formation of the gear teeth by two plates also permits the stepped arrangement illustrated in Fig. V, which enables the gear sector to cooperate more favorably with the slanting pitch of the worm. It is well known that in the usual stamping operations the under side of the cut is left with a sharp edge. By so stamping the parts 6 and 6' that the sharp edges are on the meeting surfaces of the two parts when assembled, the outer corners of the teeth -on both faces of the complete rocking member 3 are relatively smooth for cooperation with the worm.

With an adequate circumferential overlap of the two ends of the thread of the worm, it is feasible to omit the plate 6' and use only the single thickness gear formed on portion 6 of the U-shaped rocking member 3. However, the double thickness gear form has been disclosed, as it is the best form known to me for use with a stamped sheet metal worm.

In operation, motion imparted to cord 9 causes the concurrent rotation of pulley 8, shaft l0, and worm I. As the worm 1 rotates, it imparts rotarymovement to the rocking member 3 with the result that the top slat 4 of the blind is tilted. As is well understood in the art, the top slat is articulated with the other slats of the blind by means of a ladder tape or the like (not shown) so that all slats in the blind are tilted simultaneously upon the tilting of the top or tilt slat 4.

In compliance with the patent statutes I have disclosed the best form in which I have contemplated applying my invention, but it is to be understood that the disclosure herein is to be considered as illustrative and not limiting the scope of the invention.

I claim:

1. A Venetian blind fitting comprising a bracket, a worm wheel mounted on the bracket, a U- shaped rocking member formed of sheet metal, one leg of the U-member having a curved edge formed with gear teeth and pivoted to the bracket, a plate welded to the toothed leg of the rocking member and formed with teeth corresponding to the teeth of the rocking member.

2. A Venetian blind fitting comprising an angle bracket having a vertical branch and a horizontal branch, the vertical branch being formed with a partly cylindrical horizontal depression and with an opening extending across the depression, a bushing secured in the depression, a shaft in the bushing, a worm wheel secured to one end of the shaft and extending into the opening, the other end of the shaft carrying an operating device, a U-shaped rocking member having one side of the U formed with a curved upper edge out with gear teeth, the rocking member being pivoted to the bracket with the gear teeth cooperating with the worm wheel.

3. A tilter for Venetian blinds comprising a sheet metal angle bracket having a horizontal leg to be attached to a support for suspending the bracket and a vertical leg depending from the horizontal leg, the vertical leg being formed with an opening and a horizontal groove extending on opposite sides of the opening, a shaft and worm assembly positioned adjacent to said groove with the worm in said opening, a shaft-securing member of sheet metal, lying adjacent to said shaft and affixed to said vertical leg, a gear pivoted to said vertical leg and meshing with said worm, and means integral with said gear to engage the tilt slat of a Venetian blind.

4. A tilter for Venetian blinds comprising a sheet metal angle bracket having a horizontal leg to be attached to a support for suspending the bracket and a vertical leg depending from the horizontal leg, the vertical leg being formed with an opening and a horizontal groove extending on opposite sides of the opening, a shaft and worm assembly positioned adjacent to said groove with the worm in said opening, a shaft-securing member of sheet metal, lying adjacent to said shaft and affixed to said vertical leg, and a U-shaped member pivotally attached to said vertical leg of the bracket, one side of such U-shaped member being formed with gear teeth meshing with said worm and the other side being formed for engagement with the tilt slat of a Venetian blind.

5. A tilter for Venetian blinds comprising a sheet metal bracket having a groove pressed therein, a shaft, a worm on one end of the shaft, 9. driving member on the other end of the shaft, a bushing on the shaft between the worm and the driving member, said bushing being positioned in said groove in the bracket, and the bushing having an exterior circumferential groove, and a metal strap lying in said circumferential groove, said strap being secured to said bracket to hold the bushing in assembled relation with the bracket.

6. A tilter for Venetian blinds comprising a sheet metal bracket having a groove pressed therein, a shaft, a worm on one end of the shaft, a driving member on the other end of the shaft, a bushing on the shaft between the worm and the driving member, said bushing being positioned in said groove in the bracket, and the bushing having an exterior circumferential groove, and a metal strap lying in said circumferential groove, the ends of the strap being passed through slots in said bracket and being clinched against the opposite side of the bracket to hold the bushing in assembled relation with respect to the bracket.

'7. A tilter for Venetian blinds comprising a sheet metal bracket, a worm mounted. on said bracket, a U-shaped sheet metal rocker having one leg thereof positioned adjacent to said bracket and formed with teeth meshing with said worm, a sheet metal member positioned against said leg of the U-shaped rocker, and a pivot pin passing through said sheet metal member, said leg of the U-shaped rocker, and said bracket.

8. A tilter for Venetian blinds comprising a sheet metal angle bracket having a horizontal leg for attachment to a support, and having a depending vertical leg, the vertical leg having a horizontal groove pressed therein, a bushing positioned in said groove, said bushing having an external circumferential groove, a metal strap engaging the grooved portion of the bushing, the ends of the strap being passed through holes in said vertical leg of the bracket and being clinched on the opposite side thereof to secure the bushing in assembled position, a shaft journalled in the bushing, means to rotate the shaft, a worm on the shaft, and a sheet metal rocker member pivoted to the depending leg of the bracket, the rocker member having teeth meshing with said worm.

HANS K. LORENTZEN.

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