CN2271090Y - Transfomer open-circuit protection arc-extinguishing safety device for neon lamp - Google Patents

Abstract

The utility model discloses a transformer open-circuit protection arc-extinguishing safety device for a neon lamp. The utility model has the technical characteristic that the input end of the device is connected with a high-voltage output end at the auxiliary side of a booster transformer, and the output end is connected with a protective circuit; a rectifier 1 is a bridge rectifier whose two bridge arms are connected with the auxiliary side of the booster transformer; one end of the direct-current output of a rectifying bridge is connected with a voltage limiter 2; the other end is connected with the protective circuit; the voltage limiter 2 is a voltage dependent resistor device. The utility model has the advantages that the structure is simple, the sampling of an open-circuit state is accurate, fire hazard caused by high voltage discharge arcs is prevented, and the transformer of a neon lamp is protected form damaging.

Description

Gas tube sign transformer open-circuit-protection arc extinguishing safety device

The utility model discloses a kind of gas tube sign transformer open-circuit-protection arc extinguishing safety device.

In the prior art, the open-circuit-protection of gas tube sign transformer is broadly divided into two classes: a class is to utilize open circuit electrical discharge arc blowout or add thrermostatic bimetal-plate to make the bimetal leaf action force the circuit failure of oscillation.The shortcoming of this class circuit is to produce electrical discharge arc, causes fire easily; Operate time of protection long (needing the several seconds usually) causes circuit to damage easily; Can not discharge (need open replacing) automatically as blowout; If the external discharge gap less than internal discharge gap or lamp tube air leaking, then can not be protected.The operation principle of the second class open loop protection circuit is to utilize gas tube sign transformer output when open circuit, and load increases the weight of caused electric current and change in voltage, and when surpassing set point, the protective circuit action is cut off the electricity supply or made the blocking of oscillator.The shortcoming of this class circuit is: protect inaccurate, this be since during transformer operate as normal and neon light tube open circuit the electric current and the change in voltage difference of (when especially opening a way in the middle of the neon light tube) little, set point is little to cause misoperation easily, and set point does not have protective effect too greatly again; The situation that forms electrical discharge arc when opening a way for output often can not be protected.For transformer, be little when the electrical discharge arc of output is lighted neon light tube as duty ratio.

The purpose of this utility model is that sampling value of design is accurate between gas tube sign transformer high-voltage output end and protective circuit, the fast open-circuit-protection arc-control device that also can discharge automatically of response.When the gas tube sign transformer output is opened a way, the open circuit voltage of limiting transformer, and give signal of protective circuit, and control oscillation circuit, the input power supply of the failure of oscillations or cut-out gas tube sign transformer, thus the high pressure that stops gas tube sign transformer is exported.

Task of the present utility model realizes by following design.Said gas tube sign transformer open-circuit-protection arc extinguishing safety device is made up of rectifier 1 and voltage limiter 2 circuit, and its technical characterictic is: this device input termination step-up transformer secondary high-voltage output end, and output termination protective circuit.Rectifier 1 is a high pressure bridge rectifier, and two brachium pontis connect the step-up transformer secondary, and the direct current of rectifier bridge is exported a termination voltage limiter 2, another termination protective circuit, and voltage limiter 2 is varistor devices, a termination rectifier 1, another termination protective circuit.

The good effect that the utility model produced is: the open-circuit condition sampling accurately; Eliminate electrical discharge arc.Prevent the fire that causes because of electrion electric arc, and the protection gas tube sign transformer is not damaged.

Enumerate the utility model most preferred embodiment below in conjunction with accompanying drawing.

See that dashed rectangle partly is that the utility model structural principle schematic diagram also is the utility model most preferred embodiment figure among the figure, the rectifier 1 among the figure is a bridge rectifier, and voltage limiter 2 is piezo-resistances.

Usually gas tube sign transformer is by mains-supplied, 220V, the 50Hz alternating current, through becoming the direct current about 300V behind the rectifying and wave-filtering, this direct current becomes tens kilo hertzs alternating voltage by oscillating circuit, bring the voltage up to the starting voltage of lighting neon light tube by step-up transformer again, for neon light tube work.Under normal circumstances, the output high tension voltage of gas tube sign transformer is limited by the operating voltage of neon light tube.Simultaneously, this voltage is added on the voltage limiter 2 after rectifier 1 rectification.Because the puncture voltage of voltage limiter 2 is higher than the operating voltage of neon light tube, voltage limiter 2 does not have electric current to flow through.Voltage limiter 2 is inoperative.When the gas tube sign transformer high-voltage output end was opened a way, because the output voltage of gas tube sign transformer no longer is subjected to the restriction of neon light tube operating voltage, the floating voltage of gas tube sign transformer (output open circuit voltage) will raise.When floating voltage was elevated to the puncture voltage of voltage limiter 2, voltage limiter 2 punctured, and the gas tube sign transformer output voltage is spacing.Limit output end voltage on the one hand and can not continue to raise, also can not cause electrical discharge arc; The function of current that flows through voltage limiter 2 after voltage limiter 2 punctures on the other hand makes the protective circuit action to protective circuit, the cut off the electricity supply input or the control oscillation circuit failure of oscillations, thus stop high pressure output, play a protective role.After power supply was removed, protective circuit discharged automatically, if open fault is got rid of, powered up the back gas tube sign transformer again and returned to normal operating conditions.

Claims (3)

1; a kind of gas tube sign transformer open-circuit-protection arc extinguishing safety device; constituted by rectifier (1) and voltage limiter (2); it is characterized in that: this device input termination step-up transformer secondary high-voltage output end; the rectifier of this device (1) dc output end connects voltage limiter (2), the other end protective circuit of direct current output.

2; a kind of gas tube sign transformer open-circuit-protection arc extinguishing safety device according to claim 1; it is characterized in that: described high-voltage rectifier (1) is a high pressure bridge rectifier; two brachium pontis connect the step-up transformer secondary; the direct current of rectifier bridge is exported a termination voltage limiter (2), another termination protective circuit.

3, a kind of gas tube sign transformer open-circuit-protection arc extinguishing safety device according to claim 1 and 2, it is characterized in that: described voltage limiter (2) is the dc output end that a pressure-sensitive device is connected on rectifier bridge (1), another termination protective circuit.