JPH0438077Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement in a device for raising and lowering a blind by winding a lifting cord around a winding drum that moves in the axial direction while rotating together with a rotating shaft.

[Prior Art] A blind lifting device in which a lifting cord is wound around a drum that moves in the axial direction while rotating together with a rotating shaft is known from Utility Model Application No. 135490/1983. The device consists of a rotary shaft rotatably supported by a head box, a drum holder fixed to the head box, a winding drum fitted to the rotary shaft so as to be integrally rotatable and mutually slidable, and a winding drum rotatably supported by the drum holder. Consists of cover drums that are supported in a non-slidable manner relative to each other. The drum holder includes a female thread, and a male thread is provided on the circumferential surface of the winding drum. The male threaded portion is screwed into the female threaded portion from one side of the drum holder. The rotating shaft of the blind passes through the cover drum and rotates the blind as a unit, and one end of the lifting cord is locked to the external thread of the winding drum. When the rotating shaft is turned in one direction, the take-up drum is screwed into the internal thread and enters the inside of the cover drum.
At this time, the lifting cord is unwound from the externally threaded portion of the winding drum. When the rotating shaft is reversed, the male threaded portion of the winding drum is screwed back into the female threaded portion and removed from the cover drum, and the lifting cord is wound onto the male threaded portion. The lifting range of the blind depends on the length of the lifting cord wound around the external thread of the winding drum, that is, the axial length of the external thread of the winding drum. The length of the cover drum should be changed depending on the range of elevation of the blind, but preparing winding drums and cover drums of various lengths will actually increase costs. Therefore, since large items also serve as small items, only long items are prepared, and short items are not prepared. Therefore, when the blind is raised, the winding drum will be pulled out of the cover drum as much as possible regardless of the range of elevation of the blind, so the space occupied by the winding drum and cover drum in the head box will be considerably long. Become.

[Problems to be solved by the invention] As described above, in order to accommodate the winding drum and cover drum of the conventional device in the headbox, a long space is required in the axial direction, so a short blind of the headbox, For example, the width is 450mm
There was a problem that it could not be used with the following blinds.

The present invention was made to solve this problem, and its purpose is to provide a Venetian blind lifting device that requires a relatively small length of space in the head box in the longitudinal direction. be.

[Means for Solving the Problems] In order to achieve the above object, the feature of the present invention is to attach one end of the cover drum 20 to the drum holder 31, as shown in FIGS. The threaded portion 32 is fitted onto the shaft portion 34, and the other end of the cover drum 20 is extended in the direction in which the winding drum 10 slides when unwinding the lifting cord. A groove 14 extending in the axial direction is formed in the cover drum 20, and a rib 24 is provided on the inner peripheral surface 22 of the cover drum 20 to fit into the groove.
The overall length of the winding drum 10 is made much shorter than the length in the axial direction of the external threaded part of the winding drum 10 so that the winding drum 10 can penetrate the cover drum 20. Therefore, the cover drum 20 is not directly rotated by the rotary shaft 30 of the blind, but is rotationally driven via the winding drum 10.

[Function] As shown in FIG. 2, the overall length of the winding drum 10 of the device of the present invention is the same as that of the conventional device, but the overall length of the cover drum 20 is much shorter than that of the conventional device, so the winding Drum 10 and cover drum 20
Since the axial length of the space required depends on the range of elevation of the blind, the axial length within the headbox of the device of the present invention is considerably shorter than that of the conventional device. Therefore, if the vertical range of the blind is small, it can be installed and used even in narrow width blinds that could not be installed in the past.

[Example] The apparatus of the present invention will be described based on an example shown in the drawings. As shown in FIG.
A square shaft-shaped rotating shaft 30 passes through the square hole 11 . Two grooves 14 are provided in the externally threaded portion 12 of the winding drum 10, which are directly aligned. cover drum 20
has a hollow cylindrical shape, and a ratchet 21 is provided at the end on the winding drum 10 side. The winding drum 1 is disposed on the inner circumferential surface 22 of the cover drum 20 excluding the end.
Two ribs 24 are provided which fit into the grooves 14 of 0. The total length of the winding drum 10 is the same as that of the conventional one, but the total length of the cover drum 20 is less than half of the total length of the winding drum, which is significantly shorter than that of the conventional one.

As shown in FIG. 2, a drum holder 31 is fixed to the head box 40, and the male threaded portion 12 of the winding drum 10 is connected to the female threaded portion 32 of the drum holder.
is screwed in. Inner peripheral surface 22 of cover drum 20
is rotatably fitted into the shaft portion 34 on the outer periphery of the female threaded portion 32 of the drum holder 31. At this time, the fourth
As shown, the ribs 24 of the cover drum 20 fit into the grooves 14 of the take-up drum 10.

One end of the lifting cord 35 is fastened to the male thread portion 12 of the winding drum 10, and the other end is fastened to the drum holder 31.
The cord passes through the lift cord hole 33, hangs down through the slat 42, and reaches the bottom rail 44, where it is fastened.

The lifting cord 35 is hung on a stopper 36 supported by a spring 37 in the lifting cord hole 33,
Push down the stopper 36. When the lifting cord 35 is loosened, the stopper 36 rises and hits the ratchet 21 to prevent the winding drum 10 from rotating through the drum cover 20.

Although not shown, each slat is supported by a ladder cord, and the lower end of the ladder cord is hung on a bottom rail, and the upper end of the ladder cord is hung on a ring that is slidably fitted on a male threaded portion.

As shown in FIG. 2, when the rotating shaft 30 is turned in one direction and the blind is raised completely, the
0 is located at the maximum distance from the cover drum 20 and the female threaded portion 32, and the rib 24 of the cover drum 20
One end thereof fits into the groove 14 of the winding drum 10.
All of the lifting cords 35 are wound onto the externally threaded portion of the winding drum 10.

As shown in FIG. 3, when the rotating shaft 30 is reversed and the blind is completely lowered, the winding drum 10 passes through the female threaded portion 32 and enters the cover drum 20.
The degree of penetration depends on the distance the blind is raised and lowered. If the lifting distance is large, the winding drum 10 will penetrate deeply through the cover drum 20, and if it is small, the winding drum 10 will penetrate shallowly and will not penetrate. At this time, the lifting cord 35 is unwound by a length corresponding to the lifting distance from the male threaded portion 12 of the winding drum 10, and the bottom rail 44 is lowered.

The axial length of the space required within the head box 40 of the device depends on the moving range of the winding drum 10 when the vertical distance is long, and when the vertical distance is short,
It is determined by the winding drum 10 and the cover drum 20 when the blind is raised, but it is compared with the length of the space occupied by the cover drum, which is about the same length as the conventional winding drum, and the winding drum that has come out of it to the maximum extent. Then, the required length of the device is significantly reduced when the vertical distance of the blind is short, and it is considerably shortened even when the vertical distance of the blind is long. Therefore, it can be installed and used even in narrow width blinds that could not be installed in the past.

[Effects of the invention] As described above, the device of the invention rotates the cover drum integrally with the rotating shaft by fitting the ribs provided on the inner peripheral surface of the cover drum into the grooves provided on the external thread of the winding drum. Therefore, there is no need to directly fit the cover drum onto the rotating shaft, so the overall length of the cover drum is significantly shortened compared to conventional ones. Therefore, the length of space required in the axial direction in the head box of the device of the present invention is significantly reduced when the blind has a short lifting distance, and it is reduced when the blind has a long lifting distance compared to the conventional one. Although it is not a great deal, since it is still shortened, it has the special effect of being able to be used by being attached to something with a small width, that is, a short head box, which was previously impossible to attach.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing the main parts of a device according to an embodiment of the present invention, and Figs. 2 and 3 are front views showing the main parts of a Venetian blind in cross section equipped with the device shown in Fig. 1. FIG. 2 shows the blind when it is raised, and FIG. 3 shows when the blind is lowered. FIG. 4 is a sectional view taken along the - line in FIG. 2. In the figure, numeral 10 is a winding drum, 12 is a male thread, 14 is a groove, 20 is a cover drum, 22
24 is an inner peripheral surface, 24 is a rib, 30 is a rotating shaft, 31 is a drum holder, 32 is a female threaded portion, 34 is a shaft portion, 40
44 indicates a head box, and 44 indicates a bottom rail.

Claims (1)

[Claims for Utility Model Registration] 1. A rotating shaft 30 rotatably supported by a head box 40, a winding drum 10 fitted to the rotating shaft so as to be integrally rotatable and mutually slidable, and a periphery of the winding drum. Male thread part 1 provided on the surface
2, a drum holder 31 fixed to the head box, a female threaded part 32 provided on the drum holder and fitted with the male threaded part, and externally fitted onto the drum holder so as to be rotatable but immovable in the axial direction. The device is composed of a hollow cover drum 20 and a lifting cord 35 having one end fixed to the externally threaded portion and the other end fixed to the bottom rail 44, and one end side of the cover drum 20 is fixed to the above-mentioned male thread portion of the drum holder. Shaft part 3 provided with female thread
4, the other end side is extended in the sliding direction of the winding drum when unwinding the lifting cord, and a groove 14 extending in the axial direction is provided in the male threaded portion 12, and the inner circumferential surface of the cover drum 20 is A lifting device for a Venetian blind, characterized in that the cover drum is provided with a rib 24 that engages with the groove, and the overall length of the cover drum is shorter than the axial length of the external thread. 2. The lifting device for a Venetian blind according to claim 1, characterized in that the total length of the cover drum is less than half the length in the axial direction of the male threaded portion of the winding drum.