GB2120864A - Air ionizers - Google Patents

Abstract

The invention uses a free-running rotor as a means for ionising air instead of the fixed needle or needles used in known devices. A high negative voltage is led to a rotor 5 having discharge points directed to impart rotation by reaction from the stream of ionised air leaving the points. The ioniser can be seen to be working satisfactorily, and the concentration at the points is reduced because they are moving away from the ionised air, minimising the undesirable production of ozone which arises from a visible discharge. <IMAGE>

Description

SPECIFICATION Improvements to air ionizers The invention relates to devices intended to increase the quantity of gaseous ions present in the atmosphere where research has shown that an increase in negative ions over the low figure prevailing in many environments can be beneficial to some people suffering from headaches, allergies, sinus problems and the like. An increase in gaseous ions also helps to remove airborne particles and smoke. These devices commonly comprise a means of generating a high voltage, negative for most purposes, which is applied to a needle or needles exposed to the atmosphere so that the air adjacent to the tip of the needle, where the electrical charge is at a maximum, becomes ionized and is repelled from the tip causing a flow of ionized air away from the needle.A disadvantage of known types is that the discharge from a static needle causes a visible corona which produces ozone, an irritant to some medical conditions such as asthma. A further disadvantage with existing ionizers is that it is not readily apparent that they are working, and various checks are suggested in operating instructions such as bringing a neon tester close to the discharge needle.

It is the object of the present invention to overcome these disadvantages by bringing the high voltage output to a free-running rotor provided with discharge points or edges arranged against the desired direction of rotation so that the rotor is driven by reaction from the stream of ionized air leaving the points or edges. Thus it is apparent from the spinning rotor that the ionizer is working, and because the discharge points are always moving away from the ionised air, the concentration at the tip, and therefore the ozone producing corona, is reduced. A particular embodiment of the invention will now be described with reference to the accom panying drawing.

The negative output, around -7500 volts, from a voltage multiplier 1 is led through resistors 2 which limit the current to a safe value, to an electrically conductive pivot 3 situated on top of the case 4 which encloses all dangerous parts of the circuit. The electrically conductive rotor 5 is positioned on the pivot 3 and is designed to spin freely when the tips are repelled by the charged air in their vicinity. The rotor may take a variety of forms such as a single bar having points facing either clockwise or anticlock wise, or having a section providing a round leading edge and sharp trailing edge to give direction to the departing ionised air and impart a rotating motion. It may also have multiple radial arms with the same directional features or can take the form of a disc, cylinder or ball provided with discharge points to impart rotation. The current available at the rotor is limited to a safe value by internal resistors so that the rotor can be accessible to touch, but it can also be suitably shielded or manufactured of composite insulating and conductive material to avoid contact with high voltage when in use.

CLAIMS (Filed on 5th May 1983) 1. An air ioniserwhere a high voltage negative output is brought to a rotatable member having a discharge point or points arranged directionally to cause rotation of the said member by reaction from the ionised air.

2. An air ioniser as claimed in claim 1 where the output is brought to a plurality of rotatable members.

3. An air ioniser as claimed in claims 1 and 2 where a high voltage positive output is brought to the rotatable member or members.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements to air ionizers The invention relates to devices intended to increase the quantity of gaseous ions present in the atmosphere where research has shown that an increase in negative ions over the low figure prevailing in many environments can be beneficial to some people suffering from headaches, allergies, sinus problems and the like. An increase in gaseous ions also helps to remove airborne particles and smoke. These devices commonly comprise a means of generating a high voltage, negative for most purposes, which is applied to a needle or needles exposed to the atmosphere so that the air adjacent to the tip of the needle, where the electrical charge is at a maximum, becomes ionized and is repelled from the tip causing a flow of ionized air away from the needle.A disadvantage of known types is that the discharge from a static needle causes a visible corona which produces ozone, an irritant to some medical conditions such as asthma. A further disadvantage with existing ionizers is that it is not readily apparent that they are working, and various checks are suggested in operating instructions such as bringing a neon tester close to the discharge needle. It is the object of the present invention to overcome these disadvantages by bringing the high voltage output to a free-running rotor provided with discharge points or edges arranged against the desired direction of rotation so that the rotor is driven by reaction from the stream of ionized air leaving the points or edges. Thus it is apparent from the spinning rotor that the ionizer is working, and because the discharge points are always moving away from the ionised air, the concentration at the tip, and therefore the ozone producing corona, is reduced. A particular embodiment of the invention will now be described with reference to the accom panying drawing. The negative output, around -7500 volts, from a voltage multiplier 1 is led through resistors 2 which limit the current to a safe value, to an electrically conductive pivot 3 situated on top of the case 4 which encloses all dangerous parts of the circuit. The electrically conductive rotor 5 is positioned on the pivot 3 and is designed to spin freely when the tips are repelled by the charged air in their vicinity. The rotor may take a variety of forms such as a single bar having points facing either clockwise or anticlock wise, or having a section providing a round leading edge and sharp trailing edge to give direction to the departing ionised air and impart a rotating motion. It may also have multiple radial arms with the same directional features or can take the form of a disc, cylinder or ball provided with discharge points to impart rotation. The current available at the rotor is limited to a safe value by internal resistors so that the rotor can be accessible to touch, but it can also be suitably shielded or manufactured of composite insulating and conductive material to avoid contact with high voltage when in use. CLAIMS (Filed on 5th May 1983)

1. An air ioniserwhere a high voltage negative output is brought to a rotatable member having a discharge point or points arranged directionally to cause rotation of the said member by reaction from the ionised air.

2. An air ioniser as claimed in claim 1 where the output is brought to a plurality of rotatable members.

3. An air ioniser as claimed in claims 1 and 2 where a high voltage positive output is brought to the rotatable member or members.