JPS6334952B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that uses eddy current to control the screen winding speed of a roll blind that winds up a drawn-out screen using the force of a spring built into a roll pipe.

An initial torque is applied to the spring that winds up the screen of a roll blind, and when the screen is pulled out, a tightening torque corresponding to the length of the screen that is pulled out is added to that initial torque. In order to ensure reliable winding even when the screen is pulled out a little, the initial torque cannot be made too small. Therefore, when the long screen is pulled out close to its limit, the spring winding torque becomes considerably large, and the accompanying rising speed and impact of the screen are very large, causing wear and damage to the roll blind. was. To prevent this, deceleration devices that utilize fluid or friction have been used in the past, but the problem has been that fluid-based devices are expensive and relatively inexpensive friction-based devices are prone to wear.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device for controlling the winding speed of a roll blind screen, which has a simple structure, has no parts that wear out, and can be manufactured at relatively low cost.

In order to achieve the above object, the device of the present invention has a planetary gear mechanism installed in the roll pipe of the roll blind, in which the sun gear rotates together with the roll pipe when the screen is lowered, and rotates in the opposite direction to the roll pipe when the screen is rolled up. A magnet is fixed to the shaft of the sun gear, and a conductor integrated with the roll pipe is brought close to the magnet, and an eddy current is induced based on the relative movement between the magnet and the conductor when the screen is rolled up. This is characterized by controlling the rotational speed of the roll pipe.

The apparatus of the present invention will be explained based on embodiments shown in the drawings. As shown in FIGS. 1 and 2, a core rod 2 is extended along the axis of a roll pipe 1 from a stator (not shown), and a spring 3 is fitted to the core rod. One end of the spring 3 is locked to the core rod 2, and the other end is locked to a rotator integrated with a roll pipe (not shown). A brake drum 4 is fixed to the end of the core rod 2 via a pin 5, and a brake spring 6 is fitted to the drum. Insert the protrusions at both ends of the brake spring 6 into the slits of the clutch sleeve 7. The clutch sleeve 7 freely rotates in the direction of lowering the screen 15, but rotates freely in the direction of winding up the screen 15.
Even if it tries to rotate, it cannot rotate because the brake spring 6 is fastened to the brake drum 4.

A revolution shaft 8 is fixed to the clutch sleeve 7 with a set screw 9, and a revolution plate 10 is fixed to the revolution shaft. A plurality of planetary gears 12 are attached to a revolution plate 10 via a rotation axis 11 so as to be freely rotatable. Planetary gear 12
is meshed with the internal gear body 13, and the inner circumferential protrusion 25 of the roll pipe 1 is fitted into the outer circumferential groove 23 of the internal gear body to rotate both together. Internal gear body 13
A hollow disk wall 24 is provided on one side, and a lid 14 is attached to the opposite side. The planetary gear 12 is meshed with the sun gear 16, and the shaft portion 17 of the sun gear is connected to the disk wall 2.
Make it stick out from 4. A square shaft part 18 is provided on the protruding shaft part 17, and a disk magnet 20 having a square hole 19 is attached to the square shaft part. Washer 2 with disc magnet 20
6 and nuts 21 to the square shaft portion 18, and the hollow aluminum disk 22 is screwed to the disk wall 24 facing the disk magnet.

When the screen is pulled out and the roll pipe 1 is rotated, a torque corresponding to the length of the screen pulled out is accumulated in the spring 3. At this time, since the clutch sleeve 7 rotates integrally with the roll pipe 1, the sun gear 16 also rotates integrally with the roll pipe 1. Therefore, the aluminum disk 22 and the disk magnet 20
Since there is no relative movement between aluminum disk 2
2. Eddy currents that act as rotational brakes are not generated.

When the pulled out screen is released and the torque accumulated in the spring 3 is released, the spring 3 attempts to rotate the roll pipe 1 at high speed in the direction of winding up the screen. At this time, clutch sleeve 7
is prevented from rotating in the screen winding direction by the brake spring 6 and remains stationary, so the sun gear 16 is rotated by the planetary gear 12 in the opposite direction to the roll pipe 1 at twice or three times the rotational speed.
Therefore, a difference in rotational speed of three to four times occurs between the aluminum disc 22 and the disc magnet 20.
Eddy currents are generated in the aluminum disk 22 that try to reduce the difference between the two. As a result, the rotational speed of the roll pipe 1 is controlled and decelerated by the eddy current, so the screen winding speed does not increase so much, and the roll blind is prevented from being damaged by the high speed and impact during screen winding.

As shown in FIGS. 3 and 4, a conductor that generates an eddy current may be provided on the inner peripheral surface of the roll pipe. As in the previous embodiment, the shaft portion 17 of the sun gear 16
is made to protrude from the internal gear body 13, and a corner portion 18 is provided on the shaft portion. The square hole 31 at the center of the prismatic magnet 30 is fitted into the corner 18, and the magnet 30 is fastened to the shaft 17 with the nut 21 and washer 26. An aluminum ring 32 is fitted onto the inner peripheral surface of the roll pipe 1 around the prismatic magnet 30. The inner peripheral protrusion of the roll pipe 1 is fitted into the outer peripheral groove of the aluminum ring 32, and both are rotated together. As in the previous embodiment, there is no relative movement between the magnet 30 and the aluminum ring 32 when the screen is lowered, and no eddy current that brakes the rotation of the roll pipe 1 is generated. However, since the magnet 30 and the aluminum ring 32 rotate in opposite directions when winding up the screen, eddy currents are induced in the aluminum ring 32 and suppress the rotation of the roll pipe 1. As a result, the roll pipe 1 does not rotate as fast as it should, so wear of the roll blind due to high speed and damage due to impact are prevented.

In the embodiment, the magnet is attached to the shaft of the sun gear and the conductor is attached to the roll pipe, but conversely, the magnet may be attached to the roll pipe and the conductor is attached to the shaft of the sun gear.

As described above, the device of the present invention that uses eddy currents to control the rising speed of the screen has excellent durability because it does not use friction, and has a simple structure so that it can be manufactured at relatively low cost.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a main part of a roll blind equipped with a device according to one embodiment of the present invention, Fig. 2 is an exploded perspective view of the device shown in Fig. 1, and Fig. 3 is a sectional view of a roll blind equipped with a device according to an embodiment of the present invention. The corresponding figure, FIG. 4, is a sectional view taken along the - line in FIG. 3. 1: Roll pipe, 2: Core rod, 3: Spring, 7: Clutch sleeve (brake rotation axis),
8: Revolution axis, 12: Planetary gear, 13: Internal gear body, 16: Sun gear, 17: Shaft, 20: Disc magnet, 22: Aluminum disc (conductor), 30: Prismatic magnet, 32: aluminum ring.

Claims (1)

[Claims] 1. Wrap a spring around a fixedly supported core rod, insert it into a roll pipe, lock one end of the spring to the roll pipe and the other end to the core rod, and attach the screen lowered from the roll pipe to the spring. In a roll blind that is rolled up by torque, a one-sided brake is provided on the core rod that does not brake rotation in the screen lowering direction but brakes rotation in the winding direction, and a revolution axis of a planetary gear is connected to the rotation axis of the one-sided brake, An internal gear body that engages with the planet gear is integrally attached to the roll pipe, a magnet is attached to one of the shaft of the sun gear that engages with the planet gear, and an inner surface of the roll pipe, and a conductor is attached to the other. A rising speed control device for a roll blind, etc., characterized in that the devices are fixed close to each other.