IE45973B1

IE45973B1 - Improvements in or relating to vertical slat blinds

Info

Publication number: IE45973B1
Application number: IE2194/77A
Authority: IE
Original assignee: Faber Ryslinge As
Priority date: 1976-10-29
Filing date: 1977-10-27
Publication date: 1983-01-12
Also published as: NL7711479A; DK519677A; DK489476A; NO773425L; SE7711400L; FR2369409A1; AT369504B; DE2747219A1; CH623111A5; IE45973L; DK143516B; DK143516C; ATA735777A; GB1589830A

Abstract

The vertical lamellae can be rotated about their axes by means of a rotating device. This rotating device consists of an axially toothed driver shaft (1) and, situated in the trolley (2), a circle-segment-shaped crown gear (3') on a crown-gear shaft (3) which is positioned obliquely in relation to the lamella shaft. The trolleys (2) can be displaced along a support strip (not shown) and can, as a result of the oblique position of the crown-gear shaft (3), be pushed close against one another. The lamella is supported by the crown-gear shaft (3).

Description

The invention relates to vertical slat blinds with vertical laths. In such blinds, the laths may hang down from trolleys overhead shiftable along a horizontal bearer list, which said trolleys each comprise a turning mechanism in mesh with a common shaft being axially toothed and in mesh with a sector of a face gear wheel of each trolley, a shaft of each face gear wheel carrying a corresponding lath.

In the longitudinal direction of the carrier shaft, the trolleys are required to be of as small an extension as possible, so that the laths may be pushed closely together at one end of the bearer list. The trolley of an ordinary blind may for instance be 11 to 12 mm. long.

By inclining the shaft of the face gear wheel, which is normal to the plane thereof, with respect to the vertical, the radius of the face gear wheel can be further increased, because the wheels of the neighbouring trolleys may partly slide over each other, when the trolleys are pushed together at one end of the bearer list. At the -245373 same time the face gear wheel sector may exceed 180 degrees, because the teeth can freely pass under the gear shaft at the opposite side of the mesh side.

When not vertical, the face gear wheel shaft must of course be connected to the vertical lath shaft by way of a suitable coupling.

According to the invention, there is provided a vertical slat blind comprising vertical laths hanging down from Overhead trolleys which are movable along a horizontal bearer list, each of the trolleys comprising a turning mechanism in mesh with a common shaft by means of which the laths can turn about their vertical axes, the common shaft being axially toothed and in mesh with a sector of a face gear wheel of each trolley, a shaft of each face gear wheel carrying a corresponding lath and having a lower tree end constructed as or carrying a ball having the ends of one diametrical pin or two diametrically opposed pins arranged at right angles to the face gear wheel shaft, the upper free end of a shaft of each lath being constructed as or carrying a tubular sleeve made of a flexible material, the wall of the said sleeve having two diametrically opposite slots matching the pins of the ball and defining an arched hemispherical shell matching the ball and having a polar opening, the diameter of which is slightly larger than the diameter of the face gear wheel shaft.

Thus the coupling between each trolley and its lath acts as a safety coupling. A vigorous pull on the lath (by non-skilled user e.g. in a hotel room) causes the sleeve walls to bend apart from each other because of the flexibility of the sleeve material. 4S973 Thus the ball leaves the sleeve and the trolley may be moved along the bearer line and/or the face gear wheel may be turned even if the lath is blocked.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which Fig. 1 shows in perspective a trolley and a part of a carrier shaft of a preferred blind? and Fig. 2 is an exploded view of an individual main parts of the trolley of Figure 1.

An axially toothed carrier shaft 1 shown in Figure 1 passes through trolleys 2 of a blind in such a manner that the trolleys can move freely axially along the shaft.

The carrier shaft 1 is’in mesh with a face gear sector 3, exceeding slightly 180 degrees.

In a starting position of the laths at right angles to a bearer list (not shown) of the blind, which bearer list is parallel with the carrier shaft 1, the carrier shaft 1 is in mesh with the mid point of the face gear sector 3, as shown in Figure 1, and the laths can from the starting position turn about their vertical axes 90 degrees to either side by turning of the carrier shaft 1. In the starting position of the laths, the smallest extension of the face gear sector 3, which is substantially equal to the radius thereof, is situated in the longitudinal direction of the carrier shaft. Neighbouring trolleys may therefore be pushed closely together, when the smallest extension of the face gear sector does not exceed the length of the trolley. By inclining the shaft of the face gear sector, which shaft is normal to the plane thereof, with respect to the vertical, the face -4gear radius may be further increased, because the face gears may slide over each other when the neighbouring trolleys are pushed together.

The face gear sectors can therefore be rather sturdy and the toothing coarse, which will make the mechanism 5 to 10 times stronger than the worm reduction gear used in known trolleys of similar length.

The turning mechanism shown has substantially less friction loss than a corresponding worm gear mechanism, and is not like the latter self-locking. This may make the blind partly selfcorrecting. If for instance a user pushes the trolleys together without the laths having been brought in the starting position at right angles to the bearer list, the opening turning moment of two of three adjacent leths will be sufficient to turn the plane wheels a few degrees, after which, by sliding contact with the neighbouring trolley, they will turn further towards the starting position.

As shown in Figure 2, the face gear is provided with a stopping cam 4 or similar devices which, by interaction with faces of the trolley 2, prevents the laths from turning more than 90 degrees away from the starting position.

The coupling required between trolley and lath with an inclined position of the shaft of the plane wheel 3 is constructed as shown in Figure 2.

The shaft of the plane wheel 3 is at the lower end provided with a ball 32 having two diametrically opposite pins extending at right angle to the shaft. -545973 To the upper end of the lath shaft (not shown) is fastened a tubular sleeve 33 of a flexible mater Lal, for instance plastics.

The wall of the sleeve at its top defines an arched hemispherical shell of diameter substantially identical to that of the ball 32, and having a polar opening 34 of diameter slightly larger than the diameter of the shaft of the face gear. The wall of the sleeve 33 is further provided with two diametrically opposite axial slots matching the pins of the ball 32.

Due to the flexibility of the sleeve material, the ball 32 can be squeezed through the opening 34 and, when the walls of the sleeve spring back, the ball will be retained under the hemispherical shell.

The pins of the ball will, by turning of the plane wheel or the lath shaft, act as carrier portions, but the weight of the lath will keep it vertical irrespective of the position of the face gear shaft.

The shown coupling acts as a safety coupling, as a vigorous pull of the lath will make the ball 32 and the sleeve 33 slide apart before the other parts are exposed to excessive load.

Claims

1. A vertical slat blind comprising vertical laths hanging down from overhead trolleys which are movable along a horizontal < a bearer list, each of the trolleys comprising a turning mechanism in mesh with a common shaft by means of which the laths can turn about their vertical axes, the common shaft being axially toothed and in mesh with a sector of a face gear wheel of each trolley, -645973 a shaft of each face gear wheel carrying a corresponding lath and having a lower free end constructed as or carrying a ball having the ends of one diametrical pin or two diametrically opposed pins arranged at right angle to the face gear wheel 5 shaft, the upper free end of a shaft of each lath being constructed as or carrying a tubular sleeve made of a flexible material, the wall of the said sleeve having two diametrically opposite slots matching the pins of the ball and defining an arched hemispherical shell matching the ball and having a polar 10 opening, the diameter of which is slightly larger than the diameter Of the face gear wheel shaft.

2. A Venetian blind substantially as hereinbefore described with reference to the accompanying drawings.