US2230807A - Venetian blind tilter construction - Google Patents

Description

Feb. 4, 1941. LORENTZEN 2,230,807

VENETIAN BLIND TILTER CONSTRUCTION Original Filed July 15, 1938 INVENTOR #617 f? lO/F/ZfZf/Za BY m M +4 1 ATTORNEY.

Patented Feb. 4,1941

UNITED STATES VENETIAN BLIND TILTER CONSTRUCTION Hans K. Lorentzen, Montclalr, N. 1., assignor to Lorentzen Hardware Mfg. com, New York, N. Y., a corporation of New York Original application July 15, 1938, Serial No. 219,303. Divided and this application October 19, 1940, Serial No. 361.872

5 Claims. (Cl. 156 -1'l) This invention relates to Venetian blind tilting devices, and it is particularly applicable to such devices of the worm-and-gear-type. For convenience, these devices are referred to merely as 5 tilters". The invention was originally presented in my copending application Ser. No. 219,- 303 filed July 15, 1938, of which this is a division.

Among the general objects of the invention are to simplify the manufacture, reduce the proba- 10 bility of manufacturing errors, reduce the cost,

and increase the reliability of Venetian blind tilters.

Another object of the-invention is to provide a Venetian blind tilter construction that better 1 lends itself to rapid economical manufacture on.

a quantity production basis.

Further objects of the invention are to reduce the number of parts and reduce the number of manufacturing operations for Venetian blind tilters.

Variouspther objects will be apparent from the accompanying disclosure.

Fig. 1 of the drawing is a front elevation of a tilter involving the present invention, a section of the, pulley being cut away.

Fig. 2 is a side elevation partially in section, showing the tilter of Fig. 1 when viewed from the ,direction of the arrow 2.

a Fig. 3 is an isometric view of a bracket stamping incorporated in the tilter.

Fig. 4 is .an exploded view showing in unassembled relation certain parts of the tilter.

Fig. 5 is a plan view, partially in section, show ing a shaft and pulley assembly incorporated in the tilter.

Fig. 6 is a perspective view of an oscillatory cord or chain guide incorporated in the tilter.

Fig. 7 is an elevatloriof a pivot stud by which the gear is mounted."

Fig. 8 is a detail section taken on line 88 of Fig. 5.

As shown more particularly in Figs. 1 and 2, the tilter comprises a supporting bracket designatedas a wholeby ill, a worm II, a shaft l2 rotatably mounted on the bracket, and a gear l3 pivotally attached to the bracket and meshingwith the worm. On the forward end of the shaft l2 there is a pulley I4 adapted to be driven, for an example, by a cord I to rotate the worm II in either direction and thereby. oscillate gear l3. Gear 13 is formed on one leg of a U- shaped rocking member l6; and the other leg Il is slotted at II to detachably receive a tilt bar connecting 55 member (not shown) as is well understood in the art. Pivoted between the pulley l4 and the bracket l0 there is an oscillatory cord guide, designated as a whole by l3.

The supporting bracket I0 is unitary sheetmetal stamping having the various parts shown in Fig. 3. This stamping has a horizontal le 20 that is adapted to be screwed to the head bar or other supporting structure from which the Venetian blind is suspended. It also has a vertical leg 2| on which the actuating elements of the tilter are mounted. Formed between legs and 2| is an impressed rib 22 which strengthens the bracket. Approximately centrally of the vertical leg 2! there is formed a rectangular opening 23 r having its upper edge recessed at 24. On oppo-' site sides of the opening 23 the metal of the bracket is cut, and pressed into arcuate straps which form journals for the worm shaft l2. One journal is formed by arcuate straps 25 and 26 which are so pressed as to face in opposite directions, and which are separated axially of the journal by a space 21 formed by cutting out the metal of the bracket. Similarly on the other side of the opening 23 another journal is formed by arcuate straps 28 and 29 which are pressed out 5 in opposed relation and are separated axially of the journal by space 30. The vertical dimension of cut- outs 21 and 30 is greater than the diameter of shaft l2, to permit the arcuate straps to be so shaped as to'provide the Journals with radial clearance. The purpose of this clearance will be disclosed later on. Near its bottom the vertical leg 2i of the bracket is'provided with a hole iii to receive the pivot stud of the gear l3. On the forward edge of the vertical leg there is a I hook 32 to plvotally support the oscillatory cord or chain guide l9.

The shaft I2 is initially formed with a round head 33 adjacent which is a square shank portion 34 (Fig. 5). The pulley I4 is composed of two more or less conically shaped sheet- metal stampings 35, 35. These stampings have radial ribs 36 (eight shown in each stamping) which act to grip the cord l5 and prevent it from slipping on the pulley to any great extent. Each of the pulley stampings 35, 35 is provided with a centrally positioned square hole corresponding to the square shank 34 of the shaft. The stampings 35, 35 may be identical; and the diagonal of the 0 square hole in the stamping is preferably on a diameter which is located one-quarter of the distance between adjacent radial ribs. With such coordination of the square hole with the ribs, as-- sembly of the two stampings to form 'a pulley will bring the ribs 36. on one stamping in staggered relation with the ribs 33 on the other stamping,

as'shown (for example) in Fig. 4. Ribs in staggered relation grip the pulley cord more effective- I 1y than do ribs in aligned relation. After the two pulley stampings have been as- 'sembled onto the square shank portion-of the shaft l2, the axially projecting metal of the shank is swaged by a cylindrical tool, thus displacingthe metal from annular space 40 and forming an integral collar 4011. This collar tightly binds the pulley stampings 35, 35 together and permanently 'afiixes the pulley M to the shaft l2.

first assembled to the condition of Fig. 5 and then plated, the plating solution cannot be cleaned out of the crevices and it remains and causes corrosion. This difliculty is eliminated by plating the pulley discs 35, 35 and the shaft [2 (or the head 33 thereof) before assembly. Assembly does not necessitate replating as the swaging at 40 is hidden behind the pulley I4 where it is not exposed to view. Further advantage arises out of the fact that the manufacturer must supply tilters with diiferent types of pulleys, e. g. for operation with cords and for operation with bead chains. Finished pulley parts of the different .types can be stocked, and then assembled with shafts as customers orders require.

Near its center the shaft I2 is swaged to form oppositely projecting fins 42, 42. As shown in Fig. 4, these fins are wedge-shaped in their planeaxially of the shaft; and as shown in Fig. 8, they are also wedge-shaped in a cross-axial plane. On either side of the fins 42, 42 there are zones 42a, 42a which are depressed below the contour of the shaft. The purpose of these fins will be pointed out a little later.

The cord guide I!) has a disc portion 43 apertured at 48 and having atits top an instruck zone 44 perforated at 45. At the bottom, the guide is formed into a throat 46 through which the ends of the cord or chain pass; and from the throat 46 guide wings 41, 41 project upwardly to extend part way around the circumference of the pulley I4.

In assembly, the cord guide I9 is applied to the hook 32, as indicated in Fig. 4, the hole 45 being placed on the hook and the cord guide being swung downwardly so that the aperture 48 is aligtned with the journals in the bracket stamping. The worm ll, preferably a machined brass worm, is positioned in opening 23; and the free end of shaft I2 is then telescoped through aperture 48 of the cord guide, through the journal formed by straps 28 and 29, through the worm I l and into the journal formed by straps 25 and 26.

This movement is effected with fins 42', 42 positioned in a vertical plane so that they may pass through the journal clearances. When the fins 42, 42 reach the worm II, the pulley and shaft assembly are forcibly telescoped into the worm, so that the fins are forced into driving and holding engagement with the worm. Thus, mere assembly of the shaft-pulley unit with the bracket and worm, aflixes the worm to the shaft and prevents accidental withdrawal of the shaft. As fins 42, 42 enter the worm they displace metal from the worm; and the shaft depressions 42a, 42a provide space to accommodate this displaced metal. Thus, the assembly operation 'does not result in the formation of burrs at the end of which has a reduced extension-52 that passes through the hole 3i in the bracket and is riveted thereto.

It will be noted that the tilter disclosed provides a simple construction, that the parts are relatively few, and that the assembly is simple and well adapted for quantity production.

In compliance with the patent statutes, I have disclosed the best forms in which I have contemplated 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 I claim is:

1.-In a Venetian blind tilter of the type in which a worm-and-gear are assembled with a supporting structure, the worm being on a shaft having an end which projects forwardly from the supporting structure, and said forwardly projecting end of the shaft being provided with an operating pulley; the improvement which comprises: the shaft having a preformed head on its forwardly projecting end, the pulley being located behind said preformed head, and the shaft being swaged behind said pulley whereby the pulley conceals the swaging when the tilter'is in use, the swaging acting to claintp, the pulley against said preformed head.

2. In a Venetian blind tilter of the type in which a worm-and-gear are assembled with a supporting structure, the worm being on a shaft having an end which projects forwardly from the supporting structure, and said forwardly projecting end of the shaft being provided with an operating pulley; the improvement which comprises: the shaft having a preformed head 'on its forwardly projecting end and a non-circular shank behind and adjacent to said'head, the shank being enlarged with respect to the siZe of the shaft, the pulley being located on said shank in driving relation thereto, and the shank being swaged behind said pulley whereby the pulley conceals the swaging when the tilter is in use, the swaging acting to secure the pulley in place on said shank.

3. In a Venetian blind tilter of the type in which a worm-and-gear are assembled with a supporting structure, the worm'being on a shaft having an end which projects forwardly from the supporting structure, and said forwardly projecting end of the shaft being provided with an operating pulley; the. improvement which comprises: the shaft having a preformed head on its forwardly projecting end and a square shank behind and adjacent to said head, the shank being enlarged with respect to the size of the shaft, the pulley being formed of a pair of duplicate sheet metal members apertured to correspond with said shank and located on said shank, the pulley members having cord-gripping projections in staggered relation as assembled on the shank, and the shank being swaged behind said pulley whereby the pulley conceals the swaging when the tilter is in use, the swaging acting to clamp the two pulley members together and hold them in place on said shank.

4. For a Venetian blind worm-and-gear tilter, a pulley and shaft assembly comprising: a shaft having a preformed head at one end and a preformed non-circular shank portion adjacent to said head, said shank portion being enlarged with respect to the size of the shaft, and stamped sheet-metal pulley members apertured to correspond with said enlarged non-circular shank portion and telescopically related thereto, the metal of said shank being swaged to permanently attach the pulley members to the shaft.

5. For a Venetian blind worm-and-gear tilter, a

pulley and shaft assembly comprising: a shaft having a head atone end and a non-circular shank portion adjacent to said head, and stamped sheet-metal pulley members apertured to correspond with said non-circular shank portion and telescopically related thereto, the metal of said shank being swaged to permanently attach the pulley members to the shaft.

HANS K. LORENTZEN.

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