Air ioniser

The invention relates to a simple, light and portable device for air ionization and enrichment with ozone.

The disinfecting effect of the natural disinfector ozone has been known since Pasteur. Harm is only a question of the dose. In the case of inversion weather conditions (smog), ventilating the apartment brings oxygen in the air that has been used up for days out of a dome of haze or fog. Similar to ventilation systems with a high proportion of recirculated air. When the air is ionized with high voltage, UV corona creates ozone (3x 02 -> 2x 03), but this is only stable for a short time and disintegrates (2x 03 -> 3x 02), ie new oxygen molecules are formed when it disintegrates. The ionization binds dust, smoke particles, pollen and bacteria.

The following patents have been found to be state of the art:

EP 0345 498 A1 describes a disinfection device (using ozone), the high-voltage transformer contains primary and secondary windings on each leg; The concentric arrangement according to the invention minimizes the scattering and improves the coupling.

Following the state of the art in layered construction of the circuit part, high voltage and electrode part, the compact construction according to the invention contrasts with the HV transformer and electrode in the shielding housing, better coronal performance and interference suppression.

An insulating layer over the electrode causes a capacitive voltage division which reduces the high voltage on the ionization path, -on the other hand, the full high voltage for ionization is on the bare electrode according to the invention. Power is supplied via mains rectification - DC voltage - chopper (converter) at 10 kHz to 3kV; -The inventive direct triac control of the HV transformer brings fewer components, fewer losses and therefore higher operational reliability.

In EP 0538 102 A1, a complex logic circuit and thyristor control of the high-voltage transformer is used to generate 400-800 Hz in resonance; On the other hand, there is the simple triac control according to the invention, which generates a significantly higher corona at approx. 30 kHz

In CH 611 248, the high voltage is generated via rectifier, choke, inverter with thyristors and commutation circuit and fed to an ozone tube with insulated electrodes.

In US 4,863,701 A McMurray, ozone generator:

As pos 24, a block is shown as a high-voltage transformer (7500 V 30mA), at whose connections 22a and 26b connecting cables go to tubes 18a and 18b, between these two several ozone tubes made of soda glass are arranged, running parallel to one another. This arrangement probably works with mains frequency.

In EP O 246 344 A Mitsubishi, Ozonizer:

1 shows a block Pos2 as an HV transformer, operated with mains frequency according to FIG. 2, where Pos2 is an outer cylinder, FIG.

In WO 96/38229 A DKW, Modular and Low Power lonizer:

The ionization electrode consists of a wire in a tube, whereby the DC-HV is generated from a voltage converter with Power-Mos-Fet transistors in push-pull, on the primary and secondary side by means of a diode cascade as a voltage multiplier. (Fig 3a)

The push-pull converter circuit is supplied with 140 V DC from the power supply unit; a complex IC circuit is required for the oscillator and the control logic.

In WO 93/14558 A Henkel (54) Title: Power Supply shows with Pos2 AC-Supply which supplies a control circuit Pos26 via T2, this safe and complex circuit then controls the two anti-parallel connected thyristors, which are then via choke Pos 10 control the HV transformer. The secondary circuit is then in resonance with C of the electrodes, but not the primary circuit, which is only controlled by the control logic due to the lack of feedback.

The invention was based on the object of generating the high voltage for ion and ozonization without rectifying the AC mains voltage and without converters and without control logic with the smallest possible core and simple circuit.

A low plate capacitance = epsilon * area / distance was important for the electrode in order to achieve a high resonance frequency.

This task was solved with a triac, which as a bipolar power semiconductor with

AT 407 296 Β lets a diac switch through as a trigger diode. A self-oscillating triac circuit, capacitively coupled to the mains, was chosen. This is triggered by the mains frequency and supplied with energy via the series capacitor, but then oscillates periodically with the ignition point set with the variable resistor (2) and trigger diode, and in total in resonance (approx. 30 kHz depending on C).

With 9 components, including filter-C and protection-C, it is a short-circuit-proof circuit that requires, however, pulse-proof capacitors of 1500 V and frequency capability.

The sharp-edged plate electrode with the tips on the housing is the result of the UV radiation examination of the corona - and is in contrast to the round cylinders and ozone tubes corresponding to the state of the art, and is more effective.

An embodiment of the invention is shown in the drawing. 1 shows the electrical circuit, FIG. 2 shows the view in section from the front, the HV transformer being shown rotated by 45 °, FIG. 3 shows the view from above, the left side of which in section.

The air is sucked in from the side below the fan (3) and blown out over the high-voltage transformer (4) to the ionization plate (6) and through the shielding cage (7) upwards.

The electrical energy is pumped from the network via a triac oscillating circuit directly through the primary winding into the ferrite core of the high-voltage transformer as a pulse.The high-voltage winding, after being activated with the oscillating circuit, oscillates in resonance (approx. 30 kHz) as a damped oscillation until the next control pulse .

The O2 molecules in the air are ionized and ozonized to 03 on the ionization plate of the high-voltage transformer supported by the tips on the cage and ozonized to 03. The ionization plate can be round or as a polygon with bent tips. For operation with pulsating (half-wave) high voltage, the resistor (5) is replaced by a rectifier (e.g. BY 176). Like the resistor, these are glued onto the body of the high-voltage winding and surrounded by an insulated plastic. The plate on the HV transformer is centered on the cage by means of a ceramic insulating piece and is distanced up to the maximum voltage. Spark discharges can occur in pulses due to air humidity, but these are limited by the protective resistance in front of the ionization plate and by the short-circuit-proof triac oscillating circuit.

The electronic control is encapsulated in the insulating housing (1) and equipotential bonding with the mains via high-ohm resistors.

The high-voltage part is electrically shielded and separated from the insulating outer housing. The air outlet openings are offset in such a way that it is not possible to penetrate the high-voltage part

In the sample device, the high voltage was set to 20 kV, that is 20 mm for the tip-to-plate distance, with a shielding cage diameter of 100 mm. With a larger housing and a different HV winding, the high voltage can be increased as required.

The current through the ionization plate (6) can be measured at the base of the HV winding (ground point) and was 0.1 mA in the sample device.

The energy consumption of the axial fan (3) is 14 VA, that of the high-voltage part 12 VA. The sample device has the external dimensions 12 cm wide, 17 cm long, 21 cm high, weight approx. 2 kg.

An external inverter is provided for operation with DC voltage.