Roman blind without any pull rope

Abstract

A Roman blind without any pull rope includes an upper case, a blind cloth, and at least an elastic device. The upper case has a winding shaft in its interior for winding plural ropes attached on an inner surface of the blind cloth for pushing up and down for expanding or shrinking. The elastic device is deposited in the upper case, consisting of a housing and a spring fixed in the housing, a first bevel gear with a shaft and a second bevel gear with a shaft. The first and the second bevel gear engage with each other, and the elasticity of the spring is transmitted orderly to the second bevel gear, the first bevel gear, and to the winding shaft so as to pull up or lower down the blind cloth without necessity of pull ropes. The elasticity of the spring can balance the weight of the blind cloth for keeping the blind cloth stopped at one of many vertical locations.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a Roman blind, particularly to one provided with an elastic device fixed in an upper case to always supply a Roman blind with rising up strength so as to enable the Roman blind manually pushed up and down without need of pull ropes.

2. Description of the Prior Art

Conventional Roman blinds generally have an upper case, a blind cloth having its upper end fixed with the lower side of the upper case, a lower rod of the blind cloth having plural pull ropes attached vertically on the inner surface and their ends fixed in the upper case. The Roman bind cloth can be lowered down or pulled up by handling the pulling ropes.

However, the pulling ropes have a potential danger to hook up accidentally the neck of a playful child tampering with the pulling ropes. So this drawback has to be improved.

SUMMARY OF THE INVENTION

This invention has been devised to offer a Roman blind without any pull rope, which includes an elastic device instead of the pull ropes in the conventional ones for maintaining a blind cloth at any location in the vertical direction in case of pulling down and up manually by its elasticity functioning as a raising force for the blind cloth and then releasing the hand off the blind. The elastic device consists of a housing, a spring fixed in an upper case, a first bevel gear with a shaft, and a second bevel gear with a shaft engaging with the first bevel gear for transmitting elasticity to a winding shaft combined with the shaft of the first bevel gear. Then the blind cloth does not need pull ropes, possible to be manually pushed up and down to any location vertically and released manually to stop at that location because of the balanced condition caused by the elasticity of the elastic device and the weight of the blind cloth.

BRIEF DESCRIPTION OF DRAWINGS

This invention will be better understood by referring to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a first embodiment of a Roman blind without any pull rope in the present invention;

FIG. 2 is a perspective view of an elastic device in the present invention;

FIG. 3 is an exploded perspective view of the elastic device in the present invention;

FIG. 4 is a side cross-sectional view of the elastic device in the present invention;

FIG. 5 is a perspective view of the blind cloth being pushed up to shrink in the present invention; and,

FIG. 6 is a perspective view of a second embodiment of a Roman blind without any pull rope in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first preferred embodiment of a Roman blind without any pull rope in the present invention, as shown in FIGS. 1 and 2, includes an elongate upper case 10, a blind cloth 20 and an elastic device 30 as main components combined together.

The elongate upper case 10 consists of an elongate U-shaped frame 11, a shaft base 12 respectively fixed at two side ends of the frame 121, a hexagonal winding shaft 13 combined between the two shaft base 12, and a rope winding roller 14 respectively fixed beside each shaft base 12 and combined and rotating with the winding shaft 13.

The blind cloth 20 has its upper end fixed firmly with the bottom of the frame 11 of the upper case 10, a plurality of horizontal rods 21 attached equidistantly spaced apart on an inner surface, two rope ears 22 respectively bound on two side portion of each rod 21, two ropes 23 respectively fitting through the rope ears 22 of all the rods 21 in the vertical direction and having its lower end connected stably with the lower end of the blind cloth 20 and its upper end connected with two winding rollers 14 in the upper case 10 so the ropes 13 may be wound on the winding rollers 14 to force the blind cloth 20 expand down or shrink up.

The elastic device 30 is fixed properly in the frame 11 of the upper case 10, consisting of a housing 31, a coiled plate spring 32, a first bevel gear 33 and a second bevel gear 34. The housing 31 is composed of an upper plate 31a and a lower case 31b, and the upper plate 31a has a base 312 fixed on its upper surface, and the base 312 has a first shaft hole 313. The upper plate 31a further has a second shaft hole 314 perpendicular to the first shaft hole 313 and the lower case 31b has a hollow inner space 315 with an upper opening to be closed by the upper plate 31a. The bottom wall of the hollow inner space 315 has a third shaft hole 316 aligned to the second shaft hole 314.

The coiled plate spring 32 may be a whirlwind spring or a torsion spring, positioned in the hollow inner space 315 of the housing 31, having certain elasticity.

The first bevel gear 33 has a shaft 331 to fit in the shaft hole 313 of the housing 31 and having an outer end fixed with a bevel gear body 332, and the shaft 331 has its center provided with a hexagonal hole 333 to fit with so the shaft 331 may rotate the hexagonal winding shaft 13.

The second bevel gear 34 has a shaft 341 extending in the second shaft hole 314 of the housing 31 and then fixed firmly with the coiled plate spring 32 so that the elasticity of the spring 32 may rotate the second bevel gear shaft 341, which has its outer end fixed with the bevel gear body 342 to engage the first bevel gear body 332.

In using the Roman blind, referring to FIGS. 4 and 5, a user pushes up manually the bottom of the blind cloth 20 with some force, and then the blind cloth 20 may gradually move up from the bottom, forcing the horizontal rods 21 orderly folded up. At the same time, the spring 32 of the resiliency device 30 has some elasticity to be transmitted to the second bevel gear 34, which then rotates the first bevel gear 33 then the winding shaft 13, and the winding rollers 14, which then wind up the ropes 23 owing to the rope's ends connected with the lower end of the blind cloth 20. As the elasticity of the spring 32 is made to balance with the weight of the blind cloth 20, the blind cloth 20 may stop at any location if the hand of the user releases the blind cloth 20. In the same reason, the blind cloth 20 can be lowered manually down to stop at any location in case of releasing the hand.

Further, FIG. 6 shows a second embodiment of a Roman blind without a pull rope in the invention, which has almost the same structure, except one more elastic device 30 is added to the first one, reinforcing the elasticity for balancing a heavier blind cloth 20. Then a user can select the first or the second embodiment of a Roman blind without a pull rope to suit with a blind cloth of various weights.

The Roman blind according to the invention has the following advantages, as can be understood from the foresaid description.

1. It is not necessary to use a pull rope, possible to avoid potential dangers the conventional Roman blinds have.

2. The elastic device 30 supplies the blind cloth 20 with moving-up force, so it is very easy to handle the blind cloth 20 in pushing up or pull down.

3. The raising up force of the elastic device 30 can balance the weight of the blind cloth 20 so the blind cloth 20 can be stopped at any location vertically by manual handling of a user, resulting in convenient effect.

While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.

Claims

1. A Roman blind without any pull rope comprising:

An upper elongate case consisting of an elongate U-shaped frame, a winding shaft arranged in said frame:

A blind cloth having an upper end fixed with said upper case, and plural ropes attached vertically spaced apart on an inner surface, the upper end of said ropes possible to be wound up or down by rotation of said winding shaft so said blind cloth may be expanded down or shrunk up:

At least an elastic device fixed in said elongate frame of said upper case, consisting of a housing, a spring member deposited in said housing, a first bevel gear and a second bevel gear engaging with said first bevel gear, said second bevel gear connected with said spring member, said first bevel gear connected with said winding shaft, the elasticity of said spring member transmitted orderly to said first bevel gear, said second bevel gear, said winding shaft, and said ropes to said blind cloth so the elasticity may balance with the weight of said blind cloth for keeping said blind cloth at the stopped condition at one of many locations vertically.

2. The Roman blind without any pull rope as claimed in claim 1, wherein said housing is composed of an upper plate and a lower case, said upper plate having a base on its upper surface, said base having a first lengthwise shaft hole for a shaft of said first bevel gear to extend in, said upper plate having a second shaft hole perpendicular to said first shaft hole for a shaft of said second bevel gear to extend in, said lower case provided with a hollow inner space, said hollow inner space having an upper opening for said upper plate to close up, said hollow inner space having its bottom wall bored with a third shaft hole aligned to said second shaft hole.

3. The Roman blind without any pull rope as claimed in claim 2, wherein said first bevel gear has the shaft extending in said first shaft hole of said housing, and the outer end of said first bevel gear shaft fixed with a bevel gear body, said shaft having its lengthwise center portion provided with a hexagonal lengthwise hole as the same shape and size of said winding shaft, said second bevel gear has a shaft extending in said second shaft hole of said housing, said second bevel gear shaft having its outer end fixed with a second bevel gear body engaging with said first bevel gear body.

4. The Roman blind without any pull rope as claimed in claim 1, wherein said spring member is a whirlwind spring.

5. The Roman blind without any pull rope as claimed in claim 1, wherein said spring member is a torsion spring.