FR2692418A1 - Motorised venetian blind electrical supply system - in which each blind has its own battery and drive motor connected to common supply - Google Patents

Abstract

The common low voltage DC electrical supply unit (200) feeds the blinds (100) which are connected to common bus wires (300). Each blind has its own rechargeable battery (104), drive motor (102) and motor control circuit (110). The common supply unit (200) is designed to supply the charging load of the blind batteries which are normally intermittently connected to the supply unit (200). ADVANTAGE - Supply is suitable for being supplied from solar power source due to its low power requirements.

Description

 The present invention relates generally to the power supply of a plurality of motorized devices for intermittent use such as Venetian blinds.

 Conventionally, a motorized blind comprises, in a generally reduced size housing provided in its upper region, an alternating current electric motor supplied by the mains voltage via an electronic control circuit.

 This control circuit is responsible for managing, in response to commands, for example remotely controlled, the ascent, descent and change of orientation of.

blind slats.

 However, such a known solution has a number of drawbacks. First of all, an AC motor operating at high voltage, typically 220 volts, is extremely difficult to miniaturize and hardly finds its place in the blind housing. In addition, to ensure reversibility up / down, it is necessary to use an expensive double-winding motor.

Another known solution consists in using a direct current stepper motor supplied with a low voltage, typically from 3.5 to 12 volts. This low voltage is conventionally obtained with a power supply unit comprising step-down transformer connected to the mains, followed by a rectifier bridge
This solution also has a number of drawbacks. In particular, in the case where the power supply unit is located at a distance from the blind, it is necessary to provide cables between the block and the blind with large sections, in order to minimize the energy losses in these due to high currents involved. In addition, the power supply, due to the presence of a transformer, is heavy and bulky, which complicates the installation of a set of motorized blinds.

 The present invention aims to overcome the drawbacks of the prior art. To this end, the invention is based on a completely unusual use of a rechargeable accumulator, located in the awning housing and which alone supplies the motor, in combination with a fixed cable, of small section, to which the blind is permanently connected and intended to bring to the blind, permanently and regularly, a current intended solely for recharging the accumulator.

 It may be noted in this regard that, in all known situations where a rechargeable accumulator is used to power an electrical appliance, the aim sought is either to give the appliance a portable character, the source of recharging current being able to be disconnected at will, or even to deal with random or intermittent current sources (case for example of solar panels associated with buffer accumulators).

Specifically, the invention relates to an installation for the electrical supply of a plurality of fixed appliances with an intermittent electric motor, in particular motorized venetian blinds, characterized in that it comprises
a common power supply unit capable of producing a low direct voltage,
in each device, a rechargeable accumulator intended to supply by itself all the energy necessary for the operation of the engine, and a circuit for controlling the engine and recharging the accumulator,
fixed and permanent electrical connection means between the power supply unit and each of the battery control and recharging circuits,
the power supply unit having a low power determined for the sole recharging of the accumulators of all the equipment connected to said unit.

 Advantageously, the installation further comprises means for applying to the various devices, via the electrical connection means, control orders for their respective electric motors.

According to another aspect, the invention relates to an apparatus with an electric motor, in particular a motorized venetian blind, of the type comprising a direct current motor supplied at low voltage, and means for supplying power to the motor, characterized in that the means d 'diet include:
a rechargeable battery designed to supply all the electrical energy necessary for the operation of the engine,
voltage lowering and rectifying means intended to convert an AC mains voltage into a low DC voltage, these means having a low power determined for the sole recharging of the accumulator under conditions of normal intermittent use of the apparatus.

Other aspects, objects and advantages of the present invention will appear better on reading the following detailed description of preferred embodiments thereof, given by way of example and made with reference to the accompanying drawings, in which
FIG. 1 is a schematic overview of an installation comprising a plurality of motorized venetian blinds,
FIG. 2 is a schematic diagram of an electrical circuit provided in each blind box of the installation of FIG. 1,
Figure 3 is a block diagram of a blind according to another embodiment of the invention.

 Referring firstly to FIG. 1, there is shown schematically an installation comprising a plurality of venetian blinds 100.

 Each blind 100 houses, for example in a housing 100a provided in its upper region, a direct current electric motor 102, or even a stepping motor, intended to be supplied at a low voltage, for example 9 volts, a rechargeable accumulator 104 and an electric circuit for controlling the engine and charging the accumulator generally indicated at 110.

 The installation also includes, in common for all the blinds, an electrical power supply unit 200 which is connected to the mains voltage (for example 220 volts AC) and which comprises a step-down transformer 202 and a circuit rectification and smoothing 204, of conventional type per se, for delivering at output, with an appropriate power, a direct voltage for example of about 12 volts. The control circuits 110 of the various blinds are permanently connected in parallel to the power supply 200. This connection can take place, for example, in the form of a bus 300 with two conductors circulating in the room or rooms in which are located the venetian blinds 100.

 Finally, the installation optionally includes one or more control units 400 connected to the bus 300 and capable of directing orders for raising, lowering or changing the direction of the blinds 100 to all of the control circuits 110. blade tilt.

These orders are for example transmitted, according to a well known technique, by superimposing on the low DC voltage alternating or pulsed electrical signals of low amplitude.

 As a variant, provision can be made for each blind to have its own control panel connected to the associated control circuit 110.

 Referring now to FIG. 2, each electric circuit 110 of the blind mainly comprises a decoding and piloting circuit 112, a circuit 114 for controlling the charge of the accumulator 104 and a semiconductor switching stage 116 for controlling of the DC motor 102 according to the conventional technique of electronic switching.

 The decoding and control circuit receives the voltage present on the bus 300, and decodes the alternating or impulse signals to apply to the switching stage 116 the signals required to control the rotation of the motor 102 (stop, rotation in the direction of the descent, rotation in the direction of ascent) as well as its speed of rotation.

 The charge control circuit is also of the conventional type per se. It uses the DC component of the voltage permanently present on the bus 300 to recharge the accumulator 104 if necessary.

 We will now describe quantitatively the advantages provided by the present invention, compared to a solution of the prior art.

 A motorized blind of conventional design uses a DC motor operating at 12 volts and having a nominal consumption of the order of 0.5 to 1 amp. Powering such a motor from the mains requires an 8 to 10 VA transformer for lowering the voltage.

 In an accumulator solution according to the present invention, the current which must be applied to each blind is equal to the sum of the permanent leakage current of the accumulator and the current necessary for recharging it taking into account an estimated daily consumption.

 For a small accumulator, the leakage current is typically less than 100 ijA and considered here as negligible.

If we consider that the motor of a blind, requiring a power of 10 VA, is in service for a maximum of 4 minutes per day, the energy which the bus 300 must supply it over a 24-hour period is approximately 0.67
VAh The power to be supplied is therefore around 0.03 VA.

This means that a power supply 200 equipped with a transformer with a power on the order of 3 to 5
VA, to take a certain margin of safety, is sufficient to supply the electrical energy required to 100 blinds, this value being compared to the 1000 VA required in the solution of the prior art.

 Naturally, the advantages in terms of cost and space are considerable, a 5 VA power supply typically having a space of a few hundred cubic centimeters, compared to the dimensions of an electrical cabinet required to house a power supply. a power of 1000 VA.

 It will also be noted that given the very low current carried by the bus 300 (each blind consuming only a recharge current of the order of 3 mA), its section can be reduced.

 We will now describe with reference to Figure 3 another embodiment of the invention.

 In this embodiment, each blind 500 remains supplied individually by the mains voltage and comprises, in a box 500a, its own step-down block and rectifier 502, the power of which must be of the order of 0.03 to 0.05 VA. (which means a space requirement of the order of a few cubic centimeters), a control and charging circuit 510 similar to the circuit 110 of FIG. 2, an accumulator 504 and a DC motor 502.

 This variant embodiment has the essential advantage of the miniaturization of the power supply unit, which usually poses problems by its bulk when it is desired to place it in an awning housing of extremely small size. In addition, the heating caused by the transformer and the associated rectifier is minimized, and no sort of heat removal is necessary.

 Of course, the present invention is in no way limited to the embodiments described above and shown in the drawings, but a person skilled in the art will know how to make any variant or modification in accordance with his spirit.

Claims (3)

 1. Installation for the electrical supply of a plurality of fixed devices (100) with electric motor (102) with intermittent operation, in particular motorized venetian blinds, characterized in that it comprises  a common power supply unit (200) capable of producing a low direct voltage,  in each apparatus, a rechargeable accumulator (104) intended to supply all of the energy necessary for the operation of the engine, and one.  the power supply unit (200) having a low power determined for the sole recharging of the accumulators of all the apparatuses connected to said block under conditions of normal intermittent use of said apparatuses.  fixed and permanent electrical connection means (300) between the power supply unit (200) and each of the circuits (110) for controlling and recharging the accumulator, circuit (110) for controlling the engine and recharging the accumulator,  2. Installation according to claim 1, characterized in that it further comprises means (400) for applying to the various apparatuses, via the electrical connection means (300), control orders for their respective electric motors.  3. Apparatus with an electric motor (500), in particular a motorized venetian blind, of the type comprising a direct current motor (502) supplied with low direct voltage, and means for electric supply of the motor, characterized in that the means for diet include:  a rechargeable accumulator (504) intended to supply all the electrical energy necessary for the operation of the engine,  voltage lowering and rectifying means (506) intended to convert an alternating mains voltage into a low continuous voltage, these means having a low power determined for the sole purpose of recharging the accumulator under conditions of normal intermittent use of the 'equipment.