JPH0416592B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a slackness detection device for an electric blind, and more particularly, to a slackness detection device for an electric blind that detects slackness in a band-like member from which the blind is suspended.

[Prior art and problems to be solved by the invention] Most conventional electric blinds do not have any abnormality detection function, so when the blind is lowered, for example, if a part of the blind becomes an obstacle. In such a case, the operation will not stop,
The tape or thread that hangs the blinds is unwound. As a result, the above-mentioned tapes and threads become loose, which may impede the subsequent operation of the blind or cause it to malfunction.

Also, there are blinds that prevent the loosening mentioned above, but they use a micro switch to detect slack in the tape or thread, so a force above a certain level is required for the switch to turn on/off. There was a problem with the reliability of operation.

Therefore, the main object of the present invention is to provide an electric blind that can reliably detect the loosening of the tape or thread hanging the blind and control its operation without using any mechanical structure. An object of the present invention is to provide a slack detection device.

[Means for Solving the Problems] The present invention is a slack detection device for an electric blind that detects slack in a strip member for hanging a blind, and includes a movable member that moves according to the tension of the strip member and a light emitting device. A light-emitting part that emits light and a light-receiving part that receives light are provided facing each other, and the light-emitting part is configured to include a detection means for detecting whether or not a light-blocking state has been achieved by the movement of the moving member.

[Function] In this invention, the slackness of the band-shaped member that suspends the blind is optically detected, so if the blind gets caught on an obstacle and becomes unable to be lowered, the operation is stopped. You can do as you like.

[Embodiment] FIG. 3 is a diagram showing an outline of an embodiment of the present invention. First, with reference to FIG. 3, an outline of the external configuration of an embodiment of the present invention will be described. Power cord 1 and controller 2 are connected to control circuit 3. Power is supplied through the power cord 1 to operate the electric blind. The controller 2 includes a rise switch 21 for instructing the blind to rise, a stop switch 22 for instructing the blind to stop, a lowering switch 23 for instructing the blind to descend, and a slat 13 for instructing the blind to rise.
An open switch 24 for commanding opening and a close switch 25 for commanding closing slat 13 are provided. The control circuit 3 includes a microcomputer (hereinafter referred to as MPU), its peripheral circuits, a power transformer, a stabilized power supply, and the like. A DC motor 4 is connected to the control circuit 3 . The DC motor 4 is used to raise and lower the blind, and generally a geared motor is used which has a speed reduction mechanism to reduce the rotation speed of the motor and obtain an appropriate number of revolutions for raising and lowering the blind.

A rotating shaft of the DC motor 4 is connected to a winding shaft 12 via a coupling 5. The coupling ring 5 is made of anti-vibration rubber or a spring in order to prevent the vibration of the DC motor 4 from being transmitted to the winding shaft 12. Lifting units 6, 7 and 8 are connected to the hoisting shaft 12. A slack detection section built into these lifting units 6, 7, and 8 is connected to the control section 3 by a wiring member 9. The wiring material 9 also includes wiring to the geared motor 4 and wiring to the controller 2. Lifting units 6 and 8 include a winding drum 16, a ladder drum 17, and a slack detector 18 (not shown in FIG. 3), and lifting unit 7 includes only ladder drum 17. One end of a lifting tape (which may be in the form of a string) is fixed to the winding drum 16. The other end of the lifting tape 10 passes through the plurality of slats 13,
It is fixed to the bottom rail 14. The winding drum 16 winds up or unwinds the lifting tape 10 as the winding shaft 12 rotates, thereby raising and lowering the slat 13 and hodom rail 14.
In addition, the ladder drum 17 has a ladder cord 11.
One end of the ladder cord 11 is fixed, and the other end of the ladder cord 11 is fixed to the bottom rail 14. The ladder cords 11 are a set of two cords installed at an interval corresponding to the width of the slats 13, and between these two ladder cords is a horizontal ladder-shaped cord attached to each slat so as to sandwich the slats. It is tied with two strings.

The rudder drum 17 rotates as the winding shaft 12 rotates, and controls the extent to which the slats 13 are opened.
The slat 13 is a main component of the blind, and has the effect of adjusting or blocking light from the outside by changing its angle. The bottom rail 14 functions as a weight when lowering the blind and as a weight to prevent the blind from swinging due to wind or the like after lowering.

control circuit 3, DC motor 4, and lifting unit 6,
7 and 8 are head boxes 15 that constitute the outer box.
covered by.

FIG. 4 is a schematic block diagram showing the electrical configuration of an embodiment of the present invention. Next, referring to FIG. 4, the electrical configuration of an embodiment of the present invention will be described.

AC power is input to the power transformer 31 via the power cord 1. The power transformer 31 steps down the input AC power, and converts it into a low voltage stabilized power supply section 3.
2, and generates the power necessary for the control circuit 3 and the DC motor 4. A motor drive circuit 33 is connected to the MPU 34, and controls the DC motor 4 in normal rotation, reverse rotation, or brake mode according to commands from the MPU 34. The rotation sensor 35 detects the number of rotations of the DC motor 4. The angle sensor 36 detects the angle of the slat 13. The slack detection section 37 detects slack in the lifting tape 10 using an optical sensor, inputs the detection output to the MPU 34, and stops the DC motor 4 via the motor drive circuit 33.
That is, the MPU 34 sets the motor drive circuit 33 to the brake mode. The height sensor 38, which will be explained in detail later with reference to FIG. 2, detects the height of the bottom rail 14.

FIG. 1 is a diagram for explaining one embodiment of this invention, and FIG. 2 is a diagram for explaining another embodiment of this invention. In particular, FIG. 1 shows the case where the slack detection mechanism is provided independently, and FIG. 2 shows the case where it is combined with the height detection mechanism.

In FIG. 1a, the slack detection section 37 is composed of a photo interrupter 41, a moving member 42, and a spring 43. One end of the lifting tape 10 is fixed to a winding drum 16 connected to the winding shaft 12, and the other end of the lifting tape 10 passes through a hole 46 formed in a moving member 42 to the bottom rail 14. Fixed.

When the up switch 21 or the down switch 23 of the controller 2 is operated, the winding drum 16 rotates in the direction of arrow A or the direction of arrow B. At this time, if there is no abnormality in the blind, tension is applied to the lifting tape 10 due to the weight of the bottom rail 14, and this tension acts on the moving member 42 in the direction of arrow D. . Therefore, the projection 47 formed on the moving member 42 is separated from the photo interrupter 41. The photo interrupter 41 is a device in which a light emitting section 44 and a light receiving section 44 are provided facing each other, and detects whether or not there is an object between them. Therefore, when the lifting tape 10 is under tension, the photo interrupter 41 is turned on because light is not blocked.

Next, for example, if the bottom rail 14 hits an obstacle while descending and stops descending, the lifting tape 10 pulled downward by the bottom rail 14 will loosen, and the moving member 42 will move. A force in the direction of arrow C is applied by the spring 43. Therefore, as shown in FIG. 1b, the protrusion 47 of the movable member 42 enters between the light emitting part 44 and the light receiving part 45 of the photo interrupter 41 and blocks the light. The output of 41 is turned off. The detection output of the on state or off state of this photo interrupter 41 is output from the MPU 34.
is given, and the rotation of the DC motor 4 is stopped by the MPU 34.

Next, a case in which the height detection mechanism is combined with the height detection mechanism shown in FIG. 2 will be described. In FIG. 2a, a disc 49 having a slit 48 formed around the winding shaft 12 is connected to the winding shaft 12. A photointerrupter 51 is provided so that the light emitting section 54 and the light receiving section 55 are positioned with the disc 49 sandwiched therebetween. As the winding shaft 12 rotates and the disc 49 rotates, the photo interrupter 51 optically detects the discontinuation of the slit 48. This detection signal is given to the MPU 34 as an electrical signal indicating the amount of rise or fall of the lifting tape 10.

Although not shown in FIGS. 2a and 2b, a winding drum 16 is connected to the winding shaft 12. Similar to the embodiment shown in FIG. 1, one end of the lifting tape 10 is fixed to the winding drum 16, and the other end of the lifting tape 10 passes through the hole 56 formed in the moving member 52. It is fixed to the bottom rail 14. If there is no abnormality in the blind, tension is applied to the lifting tape 10 due to the weight of the bottom rail 14, and this tension applies a force to the moving member 52 in the direction of arrow F.
Therefore, the protrusion 57 formed on the moving member 52 is separated from the photo interrupter 51. Therefore, when tension is applied to the lifting tape 10, the photo interrupter 51 is turned on because light is not blocked.

On the other hand, if the bottom rail 14 hits an obstacle while descending, or if the slat 13 gets caught and the lifting tape 10 becomes slack, the moving member 52 receives a force from the spring 53 in the direction of arrow E. Therefore, as shown in FIG. 2b, the protrusion 57 of the movable member 52 enters between the light emitting section 54 and the light receiving section 55 of the photo interrupter 51 and blocks the light. The output of Raptor 51 is turned off. The detection output of the photo interrupter 51 is given to the MPU 34, and the MPU 34 stops the rotation of the DC motor 4.

[Effects of the Invention] As described above, according to the present invention, since the slackness of the band-like member suspending the blind is optically detected, the operation of the blind can be controlled based on this detection output. This makes it possible to prevent failure of the blind due to loosening of the belt member. In addition, since the loosening of the strip member is detected optically, compared to a switch that uses a switch with contacts, the mechanical force is minimal, the operation is more reliable, its use is semi-permanent, and it requires less maintenance. It has a great effect in terms of.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a slack detection device for an electric blind according to an embodiment of the present invention. FIG. 2 is a diagram showing a slack detection device for an electric blind according to another embodiment of the present invention. FIG. 3 is a diagram showing an outline of an embodiment of the present invention. FIG. 4 is a schematic block diagram showing the electrical configuration of an electric blind to which an embodiment of the present invention is applied. In the figure, 10 is lifting tape, 12
14 is a winding shaft, 14 is a bottom rail, 16 is a winding drum, 21 is a lift switch, 22 is a stop switch, 23 is a drop switch, 34 is an MPU, 37 is a slack detector, 41 and 51 are photo interrupters, 42 and 52 is a moving member, 43 and 5
3 is a spring, 44 and 54 are light emitting parts, 45 and 55 are light receiving parts, 46 and 56 are holes, 47 and 57 are protrusions, 48 is a slit, and 49 is a disk.

Claims (1)

[Scope of Claims] 1. A slack detection device for an electric blind that detects slack in a band-like member for suspending a blind, comprising: a moving member that moves according to the tension of the band-like member; and a light-emitting section that emits light. and a detection means for detecting whether or not a light-blocking state occurs due to the movement of the movable member, the detection means being provided facing a light-receiving section that receives light, and detecting the detection output of the detection means due to the movement of the movable member. A slackness detection device for an electric blind, which detects slackness of the belt-like member based on a change in the band member.