JPH0125191Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a roll blind winding/rewinding operation device, in particular, the screen drum rotated by the hand pulling operation of the cord is spring-energized in the opposite direction by rotation in the screen rewinding direction. This invention relates to a winding and rewinding device for a roll blind equipped with a spring.

Conventionally, such a roll blind is known, and a spring that biases the screen drum in a predetermined direction serves to prevent unnecessary unwinding of the screen due to its own weight and to assist in the screen winding torque. However, this spring biasing of the screen drum in the opposite direction to screen unwinding means that during unwinding, the screen always tends to wind up, making it difficult to close the screen as required or desired. so that the degree is
In order to make the screen drum stand still at any intermediate position, it is necessary to equip the screen drum transmission system with a means for preventing rotation of the screen drum due to spring bias.

Conventionally, in this type of roll blind, one way to prevent the screen drum from rotating due to spring activation is to fit a brake coil spring into a fixed drum placed in a fixed position so that it rotates together with the screen drum. There is a known structure in which the end of a brake coil spring is engaged with the edge of a groove in an arcuate cylinder. This is because the brake coil spring is tightened by the displacement of the circular cylinder as the screen drum rotates due to the spring force, tightening it against the fixed drum, preventing the screen drum from rotating due to the spring force, and preventing the cord from rotating. When the cord pulley is rotated by operation, the claw formed on the cord pulley pushes the brake coil spring in the direction of loosening.
It is designed to release the restraint caused by the above-mentioned winding and tightening, and unlike the system that uses slippable friction braking to stop unnecessary rotation of the screen drum, the screen drum can be rotated by the cord pulley when the cord is operated, in other words, the screen drum can be rotated by the cord pulley when the cord is operated. Winding and rewinding can be done easily. However, this known method has a problem in that rotation of the screen drum in the unwinding direction due to the weight of the screen is also prevented because the brake coil spring is wound tightly around the stationary drum due to the displacement of the circular arc tube. In other words, when pulling down the screen directly,
Based on the displacement of the screen drum,
Although the brake coil spring acts to restrain the screen drum and prevents the screen from being pulled down directly as described above, it is generally not possible to pull the screen directly without operating the cord. I often try to lower it;
If you try to force the screen down, you may damage it.

Therefore, in the above-mentioned type of roll blind, the brake coil spring prevents only the rotation of the screen drum in the winding direction due to spring activation, and allows the rotation of the screen drum by directly pulling down the screen. The idea is to release the screen drum by relaxing the spring.

To explain with reference to the drawings, the roll blind winding and rewinding operation device of the present invention is code 1
In a roll blind equipped with a spring 3 which is biased in the opposite direction by rotation of the screen drum 2 in the screen rewinding direction, the screen drum 2 is rotated by a manual pulling operation, and the cord pulley 4 on which the cord 1 is hung is connected to the roll blind. A concentric fixed drum 5 is disposed in a fixed position, and a brake coil spring 6 of a compression-closing type is fitted to the fixed drum 5, and the rotation of the brake coil spring 6 in the screen unwinding direction causes the cord pulley 4 to substantially A pawl 7 that is drivingly connected to the screen drum 2 and rotates the drum in a predetermined direction is provided facing the outer peripheral surface of the fixed drum 5, and one end 8 of the brake coil spring 6 is attached substantially to the screen drum 2. The cord pulley 4 is connected to the cord pulley 4, and the other end 9 is a free end, and a protrusion 10 is formed on the cord pulley 4, which is positioned on a circular motion line drawn by the claw 7 on the pulley 4 when the cord pulley 4 rotates in the screen winding direction. In the illustrated example, the cord pulley 4 has two pulley segments connected back-to-back, with a protrusion 7 formed on the pulley segment on the required side, and a brake coil attached to the cap drum 11 integrally connected to the screen drum 2. Spring 6
One end 8 of is fixed. On the other hand, the fixed drum 5 is integrated with a non-rotating center shaft 14 supported by a support 13 on a bracket 12.

In the illustrated apparatus of the present invention, when the cord 1 is manually operated to rotate the cord pulley 4 in the screen rewinding direction, the cap drum 11 of the screen drum 2 hits the cap drum 11 of the screen drum 2 with the claw 7 on the pulley 4.
is pushed and rotated in the clockwise direction in FIG. The cap drum 11 is held in a relaxed state.
As the screen drum 2 rotates in the screen rewinding direction, it idles on the fixed drum 5. When the rotation of the cord pulley 4 is stopped midway, that is, when the unwinding of the screen is interrupted at an arbitrary intermediate position, the brake coil spring 6 is activated to move the cap drum 11 based on the spring force applied by the spring 3 in the winding direction of the screen drum 2. The screen drum 2 is rolled and contracted by the drum 11 in the counterclockwise direction in FIG.
This prevents rotation of the screen in the winding direction, that is, winding up of the screen due to the activation of the spring 3.

When the cord pulley 4 is rotated by the cord 1 in the counterclockwise direction in FIG. 3, that is, in the screen winding direction, the pawl 7 on the cord pulley 4 comes into contact with the protrusion 10 on the free end side of the brake coil spring 6. The cord pulley 4 is then pushed in the same direction, and the rotation of the cord pulley 4 is transmitted to the cap drum 11 using the pawl 7 and the brake coil spring 6 as transmission media, causing the cap drum 11 to rotate together with the screen drum 2 in the screen winding direction. In this case, the brake coil spring 6 is relaxed because the protrusion 10 is pushed counterclockwise in FIG. 3 by the claw 7, and idles on the fixed drum 5.

That is, according to the present invention, the brake coil spring 6 stops only the rotation of the screen drum 2 in the winding direction due to the spring biasing of the spring 3, and when the screen drum 2 rotates in the unwinding direction, the brake coil spring 6 stops the rotation of the screen drum 2 in the winding direction. The rotation causes the brake coil spring 6 to relax and the screen drum 2 to become unrestrained. Therefore, according to the present invention, even if the screen is directly pulled down, the screen drum 2 is allowed to rotate at that time, no unreasonable tension is applied to the screen, and the screen can be rewound by the manual operation of code 1. This can be done not only by rotation of the cord pulley 4, but also by direct lowering of the screen.

There are several types of roll blinds with different dimensions, and in the case of a heavy screen, in order to prevent the screen from falling under its own weight, the spring 3 should be tightened an appropriate number of times before installing the roll blind. , and the initial torque is given to it in advance, so in this invention, the cord pulley 4 can be damaged by shocks such as when installing a roll blind.
The claw 7 is the protrusion 10 of the brake coil spring 6.
It is preferable not to contact the screen drum 2 and release the restraint of the screen drum 2. This is, for example, the fifth
As shown in the figure, while the cord pulley 4 is not being operated,
This purpose is achieved by providing a return spring 16 that biases the pawl 7 so that it always leaves the protrusion 10 of the brake coil spring 6. The return spring 16 is connected substantially to the screen drum 2 at one end and substantially to the cord pulley 4 at the other end. In the illustrated case, the return spring 16 has one end fixed to the cap drum 11 of the screen drum 2, and the other end in contact with the abutment 17 of the claw 7. 18 adjacent to cord pulley 4
A return spring 16 is housed between the pawl 7 and the arcuate piece 18.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the present invention;
Figure 2 is a disassembled perspective view of a part of the device shown in Figure 1, Figure 3 is a front view of the brake coil spring section (corresponding to the right side of Figure 1), and Figure 4 is a section of the cord pulley. FIG. 5 is a front view showing the installed state of the return spring. 1 is a cord, 2 is a screen drum, 3 is a spring, 4 is a cord pulley, 5 is a fixed drum,
6 is a brake coil spring, 7 is a pawl, 10 is a protrusion of the brake coil spring, and 11 is a cap drum.

Claims (1)

[Scope of utility model registration request] In a roll blind, the screen drum, which is rotated by manual pulling of the cord, is fixed concentrically with the cord pulley on which the cord is hung, and is equipped with a spring that is biased in the opposite direction when the screen is rotated in the unwinding direction. The drum is placed in a fixed position, a compressed and hugging type brake coil spring is fitted to the stationary drum, and the cord pulley is substantially drivingly connected to the screen drum by rotation thereof in the screen unwinding direction. A claw for rotating the drum in a predetermined direction is provided facing the outer peripheral surface of the fixed drum, one end of the brake coil spring is substantially coupled to the screen drum, the other end is a free end, and the brake coil spring is connected to the screen drum. A roll blind winding and rewinding operating device having a protrusion positioned on a circular motion line drawn by a claw on a cord pulley when the cord pulley rotates in the screen winding direction.