GB2241395A

GB2241395A - Timed switching arrangement for lighting

Info

Publication number: GB2241395A
Application number: GB9102044A
Authority: GB
Inventors: Herbert Jehle; Helmut Natterer; Michael Kraft
Original assignee: AKO Werke GmbH and Co KG
Current assignee: AKO Werke GmbH and Co KG
Priority date: 1990-01-30
Filing date: 1991-01-30
Publication date: 1991-08-28
Anticipated expiration: 2011-01-30
Also published as: GB2241395B; ITMI910196A1; FR2658377A3; DE4002597A1; ITMI910196A0; ES2029414A6; IT1247814B; FR2658377B3; GB9102044D0

Abstract

Actuation of a push button 2 causes stair well lights 1 to be energised at full intensity for a switching-on period followed by an after glow period during which lights 1 are energised at reduced intensity to act as a warning signal, a further actuation of a push button 2 during the after glow period restoring full intensity for a further switching-on period followed by a further after glow period. A triac 3 is triggered at each zero crossing of a mains supply 10 give the full intensity and at fewer zero crossings during the after glow period. If a push button 2 is actuated during a switching-on period, lights 1 may be turned off immediately or after a delay. An after glow period may also be provided in this case. If, with lights 1 off, a button 2 is operated for less or more than a certain period, the switching-on period will be respectively of a first or a longer, second duration, followed respectively by an after glow period of a third or a longer, fourth duration. The longer switching-on period may alternatively be terminated only by a further operation of a push button. <IMAGE>

Description

A Switching Arrangement The invention relates to a switching arrangement

for actuating electric lighting using- buttons, which by means of a switching element controlled by a triggering circuit switch on the lighting for a specific switching- on period and a subsequent specific afterglow period, a warning signal being produced before the end of the afterglow period. Switching devices of this type are used, for example, for the illumination of stair wells, corridors, garages or outdoor equipment.

A switching arrangement of this type is described in DE-OS 29 02 085. In this case, the warning signal is an optical or acoustic warning signal or an interruption of current. The warning signal is short and occurs only between the switching-on period and the afterglow period. The illumination operates with equal intensity during the afterglow period and the switching-on period.

A lighting arrangement is described in DE-OS 26 00 793. In this case, the flow of current for the lighting in the switching-on period and the afterglow period is effected via a separate switch in each case. It is not explained how the switching element determining the switching-on period is to be controlled.

In DE-OS 26 00 793, the lighting during the afterglow period operates with reduced intensity as compared with the switchingon period. This is not obtained by a corresponding triggering of the second switching element, but by means of a diode connected downstream of said switching element. The afterglow period can scarcely be adjusted with precision. Said period-is dependent upon the surrounding temperature, mechanical tolerances and ageing effects as well as how long the lighting was switched on for before.

In DE-OS 30 19 565 a stair well light timing switch is 1 described, in which different switching-on periods can be obtained by different periods of actuation of the button.

It is an object of the present invention to provide a switching arrangement of the above type, which produces a prolonged warning signal before a light is switched off.

This object is attained according to the invention with a switching arrangement of the above type in that, in order to act as a warning signal during the afterglow period, the lighting operates with reduced intensity in that the triggering circuit turns on the switching element at not every zero passage of the alternating mains voltage, whereas during the switching-on period, the triggering circuit turns on said switching element at each zero passage of the alternating mains voltage, and an actuation of a button during the afterglow period again turns on the switching element with each zero passage of the alternating mains voltage.

This means that the user receives not merely a short warning signal but a prolonged preliminary warning that the light is going to be extinguished. A special signal transmitter is not required to this end.

It is also expedient that no separate switching element is required for the current flow during the afterglow period. An electronic component, such as a thyristor or triac is suitable as a switching element.

As a result of the switching during zero passage, unfavourable reactive effects on the electrical mains are avoided.

During the afterglow period, the user has sufficient time, for example in the stair well, to reach the next button. If he then actuates said button during the afterglow period, then the lighting is again switched to full illumination strength. The 1 1 X.

user does not therefore have to wait until the lighting goes out in order to switch it on again.

In a preferred development of the. invention, with. the actuation of a button during a switching-on period, the triggering circuit switches the switching element and therefore the lighting off immediately or after a delay time. Consequently, the user can interrupt the switching-on time with the same button with which he switches on the lighting in cases where the further operation of the lighting is unnecessary. This allows for a saving in current.

In a further development of the invention, with a shorter actuation of the button, the switching-on period is shorter than with a longer actuation of the button. The user can thereby preselect the switching-on period which he deems necessary. With correct operation, this also leads to a saving in current. In this respect, it can also be provided that by means of a longer actuation of the button, the light is permanently switched on and only goes out when the button is actuated again.

In each case, the required button actuation is shorter than the. switching-on period.

Further advantageous developments of the invention are contained in the following description of an embodiment. In the drawings:

Fig. 1 is a circuit diagram of a stair well lighting, X Fig. 2 shows the switching procedures and Fig. 3 is a sequence diagram of the control.

A plurality of lights 1, more particularly light bulbs, as lighting and a plurality of buttons 2 for the actuation thereof are distributed in a stair well. The lights 1 are arranged in 0 1 parallel and are connected in series with an electronic switching element 3, which is formed by a triac or thyristor. The lights 1 are connected on the one hand to the zero conductor N of the mains supply. The switching element. 3 on the,other hand is co.nne-cted to the phase L of the mains supply. Also connected to the latter are the buttons 2 connected in parallel. A reversed polarity is also possible, wherein the lights are connected to the phase L and the switching element 3 and the buttons 2 to the zero conductor N.

The buttons 2 are connected to a control input 4 of a triggering circuit 5, which comprises a control output 6, to which the control electrode of the switching element 3 is connected.

The triggering circuit 5 is preferably formed by a microprocessor. For example, the CMOS microprocessor PIC 16C54 manufactured by MICROCHIP can be used. It is also-possible to use other complex logic systems in place of the microprocessor. Logic systems of this type are described in the periodical c't 1989, issue 11, pp 196 to 207. A specialised integrated circuit (ASIC), a GAL module or PAL module can be used. Fig. 3 shows the sequence of the program of the triggering circuit 5.

For the current supply, a mains power supply 7 is connected upstream of the triggering circuit 5 which is connected to the phase L. The mains power supply 7 is connected to the zero conductor N.

The mains power supply 7 comprises a series resistance R1, a rectifier diode D, a Zener diode Z and a smoothing capacitor C. A different mains power supply could also be provided.

A synchronising input 8 of the triggering circuit 5 is connected via a resistance R2 with the zero conductor N. In addition, a frequency generator 9 is connected to the triggering circuit 5.

1 i i i 4 4r k The method of operation of the described switching arrangement is approximately as follows:

When a button 2 is actuated, the triggering circuit 5 connects the switching element 9,'so that the lights 1 are illuminated. During this switching-on period, the triggering circuit 5 firstly turns on the switching element 3 with each zero passage for all half waves of the alternating mains voltage, so that the lights 1 are illuminated with full intensity. The switching element 3 ensures a rebound-free switching in the zero passage. Reactive effects on the mains N, L are thereby avoided and the service life of the lights 1 is increased. Once the switchingon period U in Fig. 2b or tS in Fig. 2d has lapsed, the triggering circuit 5 reverses the triggering of the switching element 3 so that the latter is still turned on i n the zero passages of the alternating mains voltage but no longer with each zero passage, i.e. is connected for fewer mains half waves. Consequently, the lights 1 are only illuminated with reduced intensity. Once this afterglow period t4 in Fig. 2b or t6 in Fig. 2d has lapsed, the triggering circuit 5 switches off the switching element 3, so that the lights are extinguished.

The times t3, t4, t5, t6 can be preselected by a corresponding wiring of the code inputs 10 of the triggering circuit 5 during the assembly of the switching arrangement. The switching-on period t3 is, for example, 2 min. The switching-on period t5 is, for example, 60 min. The afterglow period t4 is, for example, 10 s. The afterglow period t6 is, for example, 12 s.

If the user actuates the respective button 2 only for a comparatively short time M, which is shorter than 1.5 s for example (cf Fig. 2a), then the triggering circuit 5 recognises this and selects the switching-on period t3 and the afterglow period t4 (cf Fig. 2b).

In contrast, if the user actuates one of the buttons 2 for a longer period t2, which is greater than 1.5 s, then the triggering circuit 5 selects the longer switching-on period t5 and the afterglow period t6.

When the user actuates one of the buttons 2 again during the afterglow period t4 or t64, then the triggering circuit 5 connects the switching element 3 in such a manner that all mains half waves are connected to the lights 1 and the lights are therefore illuminated with full intensity. The switching-on period t3 or tS and the afterglow period t4 or t6 again follow.

If the user actuates one of the buttons 2 during the switchingon period t3 or t5, then the triggering circuit 5 either switches the switching element 3 off immediately or after a certain delay time, it also being possible in this case to provide the afterglow period t4 or t6 of reduced intensity.

The longer switching-on period t5 can also be coded in such a manner that is it practically permanent. The switching off is then effected by repeated actuation of one of the buttons 2.

In addition to the above-mentioned advantages, the switching arrangement according to the invention also has the advantage that i t can be easi 1 y f i tted i n pl ace of - a known automati c stai r well switching arrangement in the existing circuit of lights 1 and buttons 2. To this end, it is expedient for the switching element 3 to be connected to the phase L.

A further advantage of the described switching arrangement consists in that it has considerably reduced power consumption, for example less than 0.2 VA, as compared with conventional stair well light timing switches, which have a power consumption of, for example, 11 VA.

In the case of the described embodiment, the illumination intensity during the afterglow period t4 or t6 is constant. It h f 1 1 1 could also be provided that the illumination intensity during the afterglow period t4 or t6 rises and falls, or decreases.

Claims

1. A switching arrangement for actuating electric lighting using push buttons, which by means of a switching element controlled by a triggering circuit switch on the lighting for a specific switching-on period and a subsequent specific afterglow period, a warning signal being produced before the end of the afterglow period, wherein the arrangement is such that, in order to act as a warning signal during the afterglow period the lighting is illuminated with reduced intensity by the triggering circuit turning on the switching element at not every zero passage of the aliernating mains voltage, whereas during the switching-on period the triggering circuit turns on said switching element with each zero passage of the alternating mains voltage, and the arrangement is further such that an actuation of a button during the afterglow period again turns on the switching element at each zero passage of the alternating mains voltage.

2. A switching arrangement according to Claim 1, wherein the arrangement is such that, with an actuation of a button during the switching-on period the triggering circuit is caused to switch off the switching element and therefore the lighting, either immediately or after a delay time.

3. A switching arrangement according to one of the preceding Claims, wherein the arrangement is such that the switching-on period is maintained for- longer than the period of actuation of a button.

4. A switching arrangement according 'to one of the preceding Claims, wherein the arrangement is such that, in the case of a shorter actuation of the button the switching-on period is shorter than in the case of a longer actuation of the button.

1 j i i i 1 1 7 - 9

5. A switching arrangement according to Claim 4, wherein the arrangement is such that, as a result of a longer actuation of a button the lighting is switched on permanently and is only switched off upon a further actuation of a button.

6. A switching arrangement according to one of the preceding Claims, wherein the said switching element is an electronic switching element such as a triac or thyristor.

7. A switching arrangement according to one of the preceding Claims, wherein the triggering circuit is synchronised with the mains frequency.

8. A switching arrangement according to one of the preceding Claims, wherein the switching-on period and afterglow period are coded in the triggering circuit.

9. A switching arrangement substantially as described herein with reference to the accompanying drawings.

Published 1 99 1 at The Patent Office. Concept House. CardifT Road. Newport, Gwent NP9 1RH. Further copies may be obtained from Sales Branch. Unit 6. Nine Mile Point. Cwmfelinfach. Cross Keys, Newport, NP1 7HZ. Printed by Multiplex techniques ltd. St Mary Cray. Kent.

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