NL2010520C2

NL2010520C2 - Air duct product.

Info

Publication number: NL2010520C2
Application number: NL2010520A
Authority: NL
Inventors: Eliane Khoury; Vincent Adrian Vons; Hendrikus Johannes Timmermans
Original assignee: Virus Free Air B V
Priority date: 2013-03-26
Filing date: 2013-03-26
Publication date: 2014-09-29

Description

Air dud product

TECHNICAL FIELD

The invention relates to an air duct product for use in a ventilation system comprising an air duct having a circumferential wall and at least one high-voltage component which is arranged in the air duct. The high-voltage component could be in the form of a corona electrode or an electrostatic precipitator.

BACKGROUND

With the continuous growth of the world's population, technology and industry, increasingly larger numbers and multiple types of particulate matter, also including pathogenic micro-organisms, are generated and released into the air. Particulate matter includes further all tiny pieces of solid or liquid associated with the Earth’s atmosphere, such as soot, tobacco smoke, smog, oil smoke, fly ash, cement dust. The effects of inhaling particulate matter that have been widely studied in humans and animals now include asthma, lung cancer, cardiovascular issues, respiratory diseases, birth defects, and premature death. The air quality is therefore of particular importance for human health. Furthermore in environments where the chance of infection is high the air quality is of importance. An example of such an environment is an operating room, where patients, often with open wounds, are susceptible to aerogenic pathogenic particulate matter.

The requirements for the air quality, i.e. the quantity of particulate matter present in the air must lie below a determined maximum level, will increase further in the future.

One of the most sensitive market segments for aerogenic pathogenic particulate matter and infections resulting therefrom are hospitals, where diseases and bacteria of all types converge and are concentrated at the same location. In order to achieve high air purity, operating rooms are often connected to an air ventilation system which is equipped with air filters with a high efficiency, such as a 'High Efficiency Particulate Air (HEPA)' filter. Even such high-efficiency air filters have a limited efficiency and functional flexibility, and this affects their effectiveness under practical conditions. The efficiency of such HEPA filters thus depends on, among other factors, the flow rate, the pressure, flow speed and the heat or possibly present radiation.

Research into the situation in the Netherlands in 2005 by the Nederlands Rijksinstituut voor Volksgezondheid en Milieu (RIVM, National Institute for Public Health and the Environment) has shown that 10% to 30% of patients admitted to a Dutch hospital have hospital-related infections, 30% to 40% of which are caused by aerogenic micro-organisms.

Furthermore, statistics show that, compared to other sectors, hospital staff have the highest illness-related absence, measured both in days and in frequency.

Similarly, there are regulations in some countries to control the infection in schools. A lot of infections are spread by air. Adding an air cleaning unit to a ventilation system will help to reduce the risk of infections in buildings where a lot of humans come together.

Electrostatic precipitators (ESP’s) are widely used to remove particles from a flowing gas (such as air) using the force of an induced electrostatic charge. They function by electrostatically charging the dust particles in the gas stream by means of a corona discharge. The charged particles are then attracted to and deposited on plates or other collection devices. Although particulate matter may, depending on the origin and exposure to environmental conditions, already have a certain electrostatic charge, this charge can be markedly increased by means of ionization. A corona discharge can be used to ionize or charge air molecules. These charged air molecules, which are called ions, then attach to the airborne particulates, charging them. This corona discharge is generated by means of a high voltage applied to a set of electrodes. The thus generated electric field not only serves to charge the particles, but will also attract these charged particles to the electrode surfaces. The charged particles that are deposited on the electrode surfaces have been removed from the air. In this way the air is cleaned. To further increase the air cleaning efficiency (which in the ionizer depends on the exact configuration of the electrodes, the air velocity and the level of the high voltage used), a separate, second high voltage can be applied to two adjacent plate electrodes to generate a more efficient dust collecting field, without corona discharges. Alternatively, a so-called electret filter can be used to increase the particle capture. Such a filter has an inherent electrostatic charge or dipole polarisation which generates an electrostatic field around the filter, which attracts the charged particles to the filter and thus captures them. Other configurations, all based on the principle of electrostatic attraction to increase the capture efficiency of the airborne particulates, can be imagined as well.

ESP’s are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. Adding an ESP to an existing ventilation system requires space to install the ESP and a high-voltage cable to supply a high-voltage signal from one or more high-voltage sources to the electrodes. An electrode could be corona electrodes or a plate electrode. When the ESP is located at distance from the controller of the ventilation system, the high-voltage cable has to be protected from damage and unintended access by people. Typically a more expensive and harder to install coaxially shielded cable has to be used in order to reduce the chance of potentially interfering electromagnetic radiation emanating from the cable.

Similarly, when an “ionic wind” generator is used in a device as solid state fan, there is a high-voltage source and high-voltage cable needed to empower the corona electrode which is positioned in the duct.

SUMMARY

It is an object of the invention to provide an improved air duct product in whose duct a high voltage is used, which overcomes at least one of the disadvantages mentioned before. The invention has further at least one of the following advantages: easy to install and maintain in existing ventilation systems, reduction of the installation costs, reduction of the risk of electrocution, reduction of electromagnetic interference, reduction of the use of expensive high-voltage connectors and/or cables, improved reliability.

According to the invention, this object is achieved by an air duct product having the features of Claim 1. Advantageous embodiments and further ways of carrying out the invention may be attained by the measures mentioned in the dependent claims.

According to a first aspect of the invention, there is provided an air duct product which further comprises a high-voltage power supply configured to generate a high-voltage at an output terminal of the high-voltage power supply, wherein the high-voltage power supply is attached to the exterior of the air duct by means of a support construction. Through an opening in the circumferential wall of the air duct, a high-voltage cable couples the output terminal to the at least one high voltage component in the air duct. A shielding construction prevents unintentional access to the high voltage source and high-voltage cable. These features enable to provide a product which could easily be applied in existing ventilation systems to add an air cleaning feature to such a system. By replacing a part of the existing duct with the air duct product, no additional space is needed. As the high-voltage source is integrated in the product, the length of the high-voltage cable could be reduced. Furthermore, the shielding construction accommodates the high-voltage power supply and the portion of the high-voltage cable located outside the air duct. In this way, the risk caused by the high-voltage is reduces significantly.

In an embodiment, the high-voltage supply is arranged in a housing which is attached to the exterior of the air duct, a bottom side of the housing which is directed to the air duct comprises an opening configured for passing the high-voltage cable, the housing forming at least a part of the shielding construction and at least part of the support construction. These features enable to produce the duct with high-voltage component and the high-voltage power supply at two locations as two parts. The housing could subsequently easily be attached to the air duct. The opening in both the circumferential wall and the housing ensure that the cable is not reachable. Preferably, the edges of the openings are provided with one or more grommets, cable glands or combinations thereof, to protect the high voltage cable from damage by the edges of the openings and prevent air leaking from the air duct.

In a further embodiment, the opening in the bottom side and the opening in the circumferential wall are in line. This reduces the amount of bends in the cable and consequently the risk of damaging.

In an embodiment, the bottom side and the circumferential wall comprise surface areas which touch each other and the opening in the bottom side and the opening in the circumferential wall coincide in the surface areas which touch. In this way the length of the expensive high-voltage cable could be reduced. Furthermore, one grommet or cable gland could be used to shield the cable from damage.

In an embodiment, the support construction comprises a structure which mechanically couples the housing to circumferential wall, the structure forming a part of the shielding construction. If the openings in the circumferential wall and the housing do not touch, this feature ensures that the cable is not reachable. Furthermore, if the support is made from a conductive material, the support construction forms a part of a Faraday cage.

According to a second aspect of the invention, there is provided an air circulation system comprising a duct element having all technical features of an air duct product described above.

Other features and advantages will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, various features of embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, properties and advantages will be explained hereinafter based on the following description with reference to the drawings, wherein like reference numerals denote like or comparable parts, and in which:

Fig. 1 illustrates a longitudinal section of a first embodiment of an air duct product;

Fig. 2 illustrates a cross section of the first embodiment in Fig. 1;

Figs. 3-5 illustrate a cross section of a second, third and fourth embodiment of an air duct product;

Fig. 6 illustrates a longitudinal section of a fifth embodiment of an air duct product;

Fig. 7 illustrates a cross section of the fifth embodiment in Fig. 6;

Fig. 8 illustrates a cross section of a sixth embodiment of an air duct product;

Fig. 9 illustrates a longitudinal section of a seventh embodiment of an air duct product; and,

Fig. 10 illustrates a cross section of the seventh embodiment in

Fig. 9.

DETAILED DESCRIPTION

Fig. 1 illustrates a longitudinal section of a first embodiment of an air duct product 100. The air duct product is configured for use in a ventilation system of a building and could be regarded as a regular flow channel element with a special function. The air duct product comprises an air duct 102 having a circumferential wall 102A and at least one high-voltage component 104 which is arranged in the air duct. The high-voltage component 104 could be any device that requires a high-voltage for operation. Examples of a high-voltage component 104 are an electrostatic precipitator and one or more electrodes for generating “ionic wind”. The air duct product further comprises a high-voltage power supply 108 configured to generate a high-voltage at an output terminal 108A of the high-voltage power supply. The high-voltage power supply is positioned in a cabinet 114. The cabinet 114 comprises a lid or door (not shown) to provide access to the space in the housing for maintenance.

The high-voltage power supply is attached to the exterior of the air duct by means of a support construction. In the first embodiment, the support construction is formed by cabinet 114, a coupling part 116 which couples the cabinet to the air duct 102 and conventional coupling means to attach a printed circuit board to a surface. A high-voltage cable 110 couples the output terminal 108A to the at least one high voltage component 104 through an opening 112 in the circumferential wall 102A and an opening 114A in the side of the cabinet facing the air duct 102. A shielding construction prevents unintentional access to the high voltage source and high-voltage cable. In the first embodiment, the shielding construction is formed by the cabinet 114 and coupling part 116.

As mentioned above, the air duct product 100 is suitable for use in a ventilation system of a building. To enable this, depending of the type of coupling used in the ventilation system to couple duct parts, the air duct 102 comprises at each end 102B, 102C a coupling structure. In the first embodiment, at end 102B the air duct comprises a coupling structure having an inner circumference which corresponds to the outer circumference of the other end 102C. With this coupling structure by pushing the two ends into each other a tightly closed connection is made. It might be clear for the person skilled in the art that any suitable coupling structure to connect a pipe to the duct part 102 could be used.

Fig. 2 illustrates a cross section of the first embodiment in Fig. 1. The air duct 102 has a circular circumferential wall 102A. The coupling part 116 includes two strip-like sections. A strip-like section is attached at one side to a longitudinal side of the bottom side of the cabinet and the opposite side to the duct part. The coupling part 116 between cabinet 114 and air duct 102 shields the high-voltage cable and protects the high-voltage cable for unintentional access and damage.

The openings 112 and 114A are in line with each other. Furthermore, they are located at the shortest distance between cabinet 114 and air duct 102. It might be clear that the openings might be at any position on the bottom side of the housing 114 and the circumferential wall 102A which is surrounded by the support part 116.

Fig. 3 illustrates a cross section of a second embodiment. This embodiment differs from the first embodiment in that the air duct 102 has a square or rectangular cross section. It might be clear that in principle any suitable shape of an air channel might be used. Another difference is that the coupling part 116 is made from one metal sheet and extends along the bottom side of the housing from the left longitudinal side to the right longitudinal side of the bottom side. The coupling part 116 comprises an opening for passing the high-voltage cable. The opening in the coupling part 116 could have any suitable size and should not have necessarily the same size as the opening in the bottom side of the housing or the air duct. If the opening in the coupling part 116 is larger than the opening in the air duct 102, the opening could be used to provide access to coupling means to fixate the high voltage component 104 in the air duct 102. When the housing is attached to the coupling part, the coupling means are not accessible any more, as the housing will cover the opening. Furthermore, to protect the high-voltage cable from damage by the edges of the opening in the housing 114 and air duct 102 grommets 118 are provided between the high-voltage cable and the edges of the openings. In Fig. 3 the opening in the coupling part and the opening in the bottom side of the housing have comparable dimensions and are in line. This allows using one grommet as shown in Fig. 3. It is clear for the skilled person that a grommet could be replaced by a cable gland to protect the cable from damage. Furthermore, the grommet or cable gland provides a sealing between the edges of the opening and the high-voltage cable.

Fig. 4 illustrates a cross section of a third embodiment. This embodiment differs from the first embodiment shown in Figs. 1 and 2 in that the bottom side of the housing and the exterior of the circumferential wall 102A of the air duct 102 touch each other. The opening in the housing 114 and the opening in the circumferential wall 102A, both for passing the high voltage cable from the interior of the housing to the interior of the air duct 102, are located in the area where the housing and air duct touch each other and are in line with each other. In this embodiment and embodiments wherein the shortest distance between cabinet 114 and air duct is less than 5 cm, the ends of the space between bottom side of the cabinet 114, coupling part 116 and duct part 102 might be open.

Fig. 5 illustrates a cross section of a fourth embodiment of an air duct product. This embodiment differs from the third embodiment in the shape of the cross section of air duct 102. Furthermore, as the housing and the air duct have flat surfaces which touch each other, there is no need for the coupling part 116. This means that the housing could directly be coupled with the air duct.

Furthermore, in this embodiment only one grommet 118 is needed. The grommet covers the edges of the openings in both the bottom side of the housing and the air duct. Instead of a grommet a cable gland could be used.

Figs. 6 and 7 illustrate of a fifth embodiment of an air duct product. In this embodiment the high-voltage power supply 108 is attached to the outer side of the air duct in a conventional way by a support construction. The support construction could be in the form of three or more bolts and/or spacers. The housing 114’ covers the high-voltage power supply and the part of the high-voltage cable located exterior the air ducts. The housing 114’ is directly attached to the air duct 102. Another difference is the type of coupling structure 102B, 102C at the ends of the air duct 102. In the fifth embodiment, the coupling structure is a flange. By joining to flanges of subsequent air duct parts, an air tight seal could be obtained. In the fifth embodiment, the housing 114’ has only a shielding function and is not part of the support structure for attaching the high-voltage power supply to the air duct.

Fig. 8 illustrates a cross section of a sixth embodiment of an air duct product. This embodiment differs in the shape of the air duct compared with the fifth embodiment.

Figs. 9 and 10 illustrate a seventh embodiment. In this embodiment the support structure 116 is a folded plate. The folded plate mechanically couples the high-voltage power supply 108 to the air duct 102. Two opposite sides 116A of the folded plate are attached to the air duct 102. The folded plate further comprises a flat middle part 116B which is configured for attaching the high-voltage power supply 108. The flat middle part 116B comprises an opening 116D for passing the high-voltage cable. In this embodiment, the opening in the folded plate is substantially larger than the opening in circumferential wall 102Aof the air duct 102. This opening provides access to fixing means to fixate the high-voltage component 104 in the air duct. The flat middle part 116B forms the bottom side of the housing in which the high-voltage power supply is mounted. A cover 114” is attached to the support structure. The cover 114” could also be in the form of a folded plate. The cover 114” is configured to provide the remaining sides of the housing. In Fig. 9 can be seen that two opposite sides of the housing are folded ends 116C of the support structure 116. Thus, the support structure 116 provides three of the six sides of the housing and the cover 114” provides the three remaining sides of the housing.

In the seventh embodiment, there is an elongated space between the support structure 116 and the circumferential wall 102A. The lateral sides of the space are formed by the circumferential wall and the support structure. The end sides of the space are open. However, as the shortest distance between the flat middle part 116B and the circumferential wall is about 1 cm or less, there is almost no risk that a person could unintentionally damage the high-voltage cable in said space. In this embodiment the folded plate is the support structure and the folded plate and cover form the shielding construction.

If the material of the air duct 102, cabinet 114 and support structure 116 is from a conductive material, they form at least partially a cage of Faraday for the high-voltage parts. In this way, the amount of electromagnetic interference could be reduced.

The embodiments have the advantage that the high-voltage cable is shielded by the housing and/or coupling structure. In this way, the cable is almost not reachable from outside. This reduces the risk of damaging the cable and subsequent risks such as fire, short-circuit, electrocution. Furthermore, the risk that the cable is disconnected is eliminated.

Another advantage of having the high-voltage power supply and high-voltage component integrated into one product is that there is no need to use expensive high-voltage connectors.

As the high-voltage power supply is integrated in the product, the product only needs a connection to a mains. This could be done by inexpensive power supply cable. Optionally, the air duct product could comprise a fan; in that case a controller to control the fan speed could be accommodated in the housing together with the high-voltage power supply.

By means of the coupling structures at each end of the air duct, the air duct product could easily be integrated in an existing ventilation system. A duct part anywhere in the systems has to be replaced by the air duct product described in this application to add for example an air cleaning feature to particular rooms of the buildings. Only a power supply cable to a mains or control unit of the ventilation systems has to be installed to empower the air duct product.

The air duct product described in the present application could be in the form as a solid state fan. Such an air duct product could be used as a component in other applications and other electronic devices that uses “corona wind” to generate a flow of air/gas. In an air cleaning device, the “corona wind” is used to move air with particulate matter through a filter. In another application, the flow of gas is used to transfer heat. In those cases we have an electronic device comprising a duct component or module having all technical features of an air duct product as described in the present application.

While the invention has been described in terms of several embodiments, it is contemplated that alternatives, modifications, permutations and equivalents thereof will become apparent to those skilled in the art upon reading the specification and upon study of the drawings. The invention is not limited to the illustrated embodiments. Changes can be made without departing from the idea of the invention.

Claims

An air duct product (100) comprising an air duct (102) with a peripheral wall (102A) and at least one high-voltage component (104) arranged in the air duct, characterized in that the air duct product further comprises: - a power supply (108) configured to generate a high voltage at an output terminal (108A) of the high voltage power supply, the high voltage power supply being attached to the outside of the air duct by means of a support structure; - a high-voltage cable (110) which connects the output terminal to the at least one high-voltage component through an opening (112) in the circumferential wall; and, - a shielding structure configured to prevent unintended access to the high-voltage power supply and the high-voltage cable.

The air duct product according to claim 1, wherein the high voltage power supply is arranged in a housing which is attached to the outside of the air duct, a bottom side of the housing which is directed to the air duct comprises an opening configured to pass the high voltage cable, the housing forms at least a part of the shielding structure and the at least a part of the supporting structure.

The air duct product according to claim 2, wherein the opening in the underside and the opening in the peripheral wall are spaced apart by less than 5 cm.

The air duct product according to claim 3, wherein the opening in the bottom and the opening in the circumferential wall are located in surface portions of the bottom and the circumferential wall that are closest to each other.

The air duct product according to claim 3 or 4, wherein the opening in the bottom side and the opening in the circumferential wall are aligned.

The air duct product according to any of claims 2-5, wherein the support structure comprises a structure (116) which mechanically connects the housing to the peripheral wall, the structure (116) forming a part of the shielding structure.

The air duct product according to claim 6, wherein the structure (116) is a folded plate with two opposite sides attached to the air duct (102), a flat center portion is configured to attach the high voltage power supply (108) or a cabinet (114), which is configured to accommodate the high voltage power supply, the flat center portion includes an opening for passing the high voltage cable.

The air duct product of claim 7, wherein the center portion of the structure (116) forms the bottom of the housing.

The air duct product according to any of claims 7-8, wherein the two opposite sides of the housing are folded ends of the structure (116).

The air duct product according to any of claims 7-9, wherein the housing further comprises a cover (114 ") attached to the structure (116) and forming the remaining sides of the housing.

The air duct product according to any of claims 1-10, wherein the air duct has a circular cross section.

The air duct product according to any of claims 1-10, wherein the air duct has a rectangular cross section.

The air duct product according to any of claims 1-12, wherein the shielding structure further houses a control member.

The air duct product according to any of claims 1-13, wherein the high voltage component is at least one of a corona electrode, an electrostatic filter, and an electrostatic dust trap.

The air duct product according to any of claims 1-14, wherein the peripheral wall and the shielding structure are made of a conductive material.

The air duct product according to any of claims 1-15, wherein the air duct (102) at each end (102B), (102C) comprises a coupling structure which is configured for coupling the air duct product to another air duct.

An air circulation system comprising a channel element with all technical characteristics of an air channel product according to one of claims 1 to 16.