SU862409A1 - Device for switching-on reserve incandescent lamp - Google Patents

Description

(54) DEVICE TO INCLUDE BACKUP

one

The invention relates to electrical engineering and can be used in lighting devices of increased reliability with redundant light sources.

Devices for backing up incandescent lamps 1 are known, comprising a main and a backup incandescent lamps, a choke, a capacitor, a switching semiconductor element.

The drawbacks of the device are low noise immunity due to spurious inclusions of the backup lamp with impulse noise.

The closest in technical essence to the proposed device is a device 2 comprising a relay with sealed contacts (reed switch) and a main lamp connected to the power supply terminals through the reed switch control winding and a backup lamp connected to the power supply terminals through normally closed reed switch contacts.

The disadvantages of the device include the fact that the contacts of the reed switch are included in the power circuit of the backup lamp and each time the device is turned on, it passes through the contacts

a large starting current of the lamp, which causes rapid wear and reduces the reliability of the device.

The aim of the invention is to increase the reliability of the device.

1a is supplied so that the device for BK.iKi; riih ;; :) A reserve incandescent lamp containing a relay with sealed contacts (reed switch), the control winding of which is connected to the main lamp power supply circuit, is equipped with a resistor, a transistor and a polarized relay with two control windings, one of which is connected in parallel to a circuit of serially connected normally closed the contacts of the polarized relay and the control winding of the reed switch, and another 15 ha, through a transistor, are connected in parallel to the chain of series-connected resistors and normally open contacts of the reed switch connected in parallel to the normally open contacts of a polarized relay included in

Claims (2)

20, the power supply circuit of the backup lamp, the base of the transistor being connected to the connection point of the resistor with the contacts of the reed switch. The drawing shows a schematic diagram of the device. The device for switching on the backup incandescent lamp 1 contains a relay with sealed contacts (reed switch) 2 connected via a resistor 3 in parallel with normally open contacts 4 of a polarized relay connected to the power supply circuit of lamp 1. Normally closed contacts 5 of a polarized relay are connected in series with control winding 6 reed switch 2 into the power supply circuit of the main lamp 7. The control winding 8 of the polarized relay is connected in parallel to the contacts 5 and winding 6, and the control winding 9 of the polarized relay through transistor 1 0, connected to the connection point of the resistor 3 with the reed switch 2, is connected in parallel with the contacts 4. The device operates as follows. In the initial state, the windings 8 and 9 of the polarized relay are de-energized, its contacts 5 are closed, and contacts 4 are open. Contact reed switch 2 open. When the power is supplied, the current passes through the lamp 7, the closed contacts 5, the control winding 6 by the reed switch 2. Due to the magnetomotive force, the contacts of the reed switch 2 are closed and the base of the transistor 10 is connected to the minus of the power supply. The transistor 10 is closed. In the event of failure of the lamp 7, the current through the control winding 6 by the reed switch 2 is stopped, the contacts of the reed switch 2 are opened, the transistor 10 is opened, the current passes through the winding 9 of the polarized relay, the contacts 5 of the polarized relay open, and the lamp 4 1 to the power source. At the same time, the contacts 4 bypass the winding 9 of the polarized relay and the transistor 10, which remain de-energized. If the main lamp circuit 7 was broken temporarily. THEN when restoring, its current will pass through the winding 8 of the polarized relay, the contacts 4 of the latter are open, and the contacts 5 will close and thus the main lamp 7 will be again connected to the power source. Since the contacts of the reed switch 2 in the device are not included in the power circuit of the backup lamp 1, but in the control circuit of the transistor 10, a large switching current does not pass through them, which allows to increase the reliability of the device. The invention includes a backup incandescent lamp, comprising a relay with sealed contacts (reed switch), the control windings of which are connected to the power supply circuit of the main lamp, characterized in that it is equipped with a resistor, a transistor and a polarized two-winding relay in order to increase reliability. control, one of which is connected in parallel to the circuit from the series-connected normally closed contacts of the polarized relay and the control winding of the reed switch, and the other is connected via a transistor to a parallel chain of series-connected resistor and a normally open reed switch contacts connected in parallel normally open contacts polarized relay included in the spare lamp power circuit, wherein the transistor base is connected to the junction of the resistor with the reed switch contacts. Sources of information taken into account in the examination 1. USSR author's certificate number 403123, cl. H 05 B 39/10, 1972. 2. US patent number 3636404, cl. 315-87, 1973.