JPH0422713Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device that prevents the slats of a Venetian blind from rotating due to being blown away by wind or the like.

[Prior Art] Each slat of a Venetian blind is placed on a ladder-like string or band, and the two upper ends of the ladder-like string or band are latched to a drum or joined in a ring shape to the drum. When the shaft is rotated, each slat is tilted at the same time.

If the rotating shaft is rotated via a self-locking transmission mechanism such as a worm, there is no risk of the rotating shaft rotating even if the slat is exposed to wind, etc. However, if the rotating shaft does not have a self-locking mechanism, the rotating shaft will rotate. A problem arises in that the angle of the slat changes.

In order to prevent this, Utility Model Application No. 57-131994 fixed a split sleeve to the drive wheel of the rotating shaft, fitted a coil spring brake to the split sleeve, and fitted an inner peripheral brake drum to the coil spring brake. , the brake drum is fixed to the head box, and the split sleeve pushes both ends of the coil spring brake in the direction of contraction, while the rotation shaft is pushed in the direction of expansion of the coil spring brake, thereby regulating the rotation of the rotation shaft. is disclosed.

[Problem to be solved by the invention] The above device fixes the split sleeve to the drive wheel, so it is sufficient if there is a space near the drive wheel, but if there is no space near the drive wheel, it cannot be installed. I can't.

An object of the present invention is to provide a rotation regulating device that can be installed at any position between the drive wheel and the slat rotation mechanism on the rotating shaft, regardless of the drive wheel.

[Means for Solving the Problems] In order to achieve the above object, the feature of the present invention is to divide the rotating shaft 12 into a driving shaft 12a and a driven shaft 12b, as shown in FIG. , driven side 1
The split sleeve 30 is fitted to the shaft end of the shaft 2b so as to rotate together, and the drive side shaft body 16 equipped with the circular arc protrusion 14 having the same outer diameter and inner diameter as the split sleeve is fitted to the end of the drive side shaft 12a. The shaft body is passed through the shaft hole of the brake drum 20 and rotatably supported, and a coil spring brake 22 having both ends protruding in the radial direction is fitted on the outer periphery of the brake drum.
0 is fixed to the head box 10, and the protrusions at both ends of the coil spring brake 22 are arranged between the arcuate protrusion 14 and the split sleeve 30.

[Operation] Both ends 22a, 22b of the coil spring brake 22
do not intersect when viewed in the axial direction, so when the drive side shaft 12a is rotated, the arcuate protrusion 14 pushes either end 22a, 22b of the coil spring brake in the direction in which the coil spring brake 22 expands. The frictional resistance between the inner peripheral surface of the coil spring brake and the outer peripheral surface of the drum is reduced, and the coil spring brake rotates together with the drive-side shaft 12a to rotate the split sleeve 30. Therefore, the rotation is transmitted to the driven shaft 12b.

When trying to rotate the driven shaft 12b, the split sleeve 30 hits both ends 22 of the coil spring brake.
Since the coil spring brake 22 pushes one of the coil spring brakes a and 22b in the direction of contraction, the inner peripheral surface of the coil spring brake is tightened to the outer peripheral surface of the drum, and the split sleeve 3
0, that is, rotation of the driven side shaft 12b is prevented.

[Example] The present invention will be described based on an example shown in the drawings.

As shown in FIG. 1, a rotating shaft with a hexagonal cross section extending longitudinally inside the head box 10 of a Venetian blind is divided into a driving shaft 12a and a driven shaft 12b, and an arcuate projection 14 is attached to the end of the driving shaft 12a. The drive-side shaft body 16 equipped with the drive-side shaft is fitted so as to rotate together with the drive-side shaft. The drive side shaft body 16 is a drum 20
The drum 20 is rotatably supported by a shaft hole in the head box 10, and the drum 20 is fixedly supported by a bracket 18 fixed to the head box 10.

A driven shaft body 32 having a split sleeve 30 is fitted onto the driven shaft 12b so as to rotate together with the driven shaft, and the driven shaft body 32 is rotatably supported in the shaft hole of the bracket 18.

A coil spring brake 22 is installed on the outer peripheral surface of the drum 20.
are fitted, and both end portions 22a and 22b protrude in the radial direction without intersecting when viewed from the axial direction.

As shown in FIG. 2, the inner and outer diameters of the circular arc protrusion 14 of the drive-side shaft body 16 and the split sleeve 30 are the same, and both ends 22a and 22b of the coil spring brake 22 fit into the circumferential gap between the two. . The inner diameter of the coil spring brake 22 and the outer diameter of the brake drum 20 are approximately the same.

As shown in FIG. 3, one end surface of the brake drum 20 has the same shape as the side end surface of the bracket 18 except for a part, and the brake drum 20 is connected to the bracket 18 through a screw 24.
Fixed.

As shown in FIG. 4, each slat 40 of the Venetian blind is held between two or more weft threads of a ladder string 42, and the upper ends of the two ladder strings 42 are locked to hooks 44. is fitted into a ring 46 fixed to the driven shaft 12b so as to rotate by friction. When the driven shaft 12b rotates, the hook 44 rotates together with the driven shaft until it hits the stopper 11 on the bottom of the head box 10, so that the inclination of the slat 40 can be adjusted as shown by the dashed line.

When the drive shaft is rotated to adjust the inclination of the slat, the arcuate protrusion 14 moves toward both ends 22a of the coil spring brake 22, as shown by arrows in FIG.
22b in the direction in which the coil spring brake 22 expands, the frictional contact between the inner peripheral surface of the coil spring brake 22 and the outer peripheral surface of the brake drum 20 is loosened, the coil spring brake 22 rotates together with the arcuate protrusion 14, and The split sleeve 30 also rotates, and the rotation is transmitted to the driven shaft.

On the other hand, when the slats are blown by the wind and tension is applied to the ladder cord, and an attempt is made to turn the hook and ring to rotate the driven shaft, the split sleeve 30 acts as a coil spring brake, as shown by the arrow in FIG. 2
Since the coil spring brake 22 pushes one of both ends 22a and 22b of the brake drum 20 in the direction of contraction, the coil spring brake 22 tightens on the outer peripheral surface of the brake drum 20 and prevents the split sleeve 30 from rotating. cannot rotate. Therefore,
The slope of the slats will not change due to wind.

[Effects of the invention] The device of the present invention prevents the rotating shaft from rotating even if the slats of the Venetian blind are affected by wind, etc. Unlike conventional braking devices, this brake drum has the excellent effect of being able to be installed at any position as long as there is space for the brake drum between the drive wheel of the rotary shaft and the slat drive mechanism in the head box.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of a blind equipped with a device according to an embodiment of the present invention, and FIG.
3 is a side view of the drive side of the device shown in FIG. 1, FIG. 4 is a side sectional view of the main part showing the slat tilting mechanism of the blind shown in FIG. 1, and FIG. 5 is a side view of the device shown in FIG. 1 from the drive side. FIG. 6 is a sectional view showing a state of rotation transmission, and FIG. 6 is a sectional view showing a state of regulating rotation from the driven side. In the figure, numeral 10 is a head box, 12
12a is a rotating shaft, 12a is a drive side shaft, 12b is a driven side shaft, 14 is an arc projection, 16 is a drive side shaft body, 18 is a bracket, 20 is a brake drum, 22 is a coil spring brake, 22a, 22b are ends, Reference numeral 30 indicates a split sleeve, and 32 indicates a driven shaft body.

Claims (1)

[Claims for Utility Model Registration] 1. A Venetian blind comprising a head box 10, a rotating shaft 12 rotatably supported by the head box, and a slat tilting mechanism provided on the rotating shaft, in which the rotating shaft is Driven side shaft 12 provided with a slat tilting mechanism
b and a drive-side shaft 12a that rotates it, and the respective shaft portions of the drive-side shaft body 16 and the driven-side shaft body 32 are fixed to the drive-side shaft and the driven-side shaft so as to face each other in the axial direction. The split sleeve 30 is protruded from one of the driving side shaft body shaft portion and the driven side shaft body shaft portion, and the circular arc protrusion 14 that loosely fits into the slit of the split sleeve is protruded from the other side, and the side on which the circular arc protrusion 14 is provided. The shaft portion of the shaft body 16 is rotatably supported in the shaft hole of the brake drum 20, and a coil spring brake 22 is fitted onto the outer peripheral surface of the brake drum, and both ends 22a,
22b protrudes in the radial direction, the brake drum is fixed to the bracket 18, the bracket is fixed to the head box 10, the split sleeve 30 is rotatably supported in the shaft hole of the bracket 18, and the slit of the split sleeve is Both ends 22a, 22b of the coil spring brake 12 are inserted into the gaps on both sides of the circular arc protrusion 14.
Venetian blind rotation axis regulating device. 2. The Venetian blind rotating shaft regulating device according to claim 1, wherein the arcuate protrusion 14 and the split sleeve 30 have the same inner and outer diameters.