AU784057B2

AU784057B2 - Air filter holder

Info

Publication number: AU784057B2
Application number: AU11959/02A
Authority: AU
Inventors: Paul Facoory
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-01-22
Filing date: 2002-01-22
Publication date: 2006-01-19
Anticipated expiration: 2022-01-22
Also published as: AU1195902A; NZ509475A

Description

AUSTRALIA

Patents Act 1 990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Applicant(s): PAUL FACOORY Actual Inventor(s): P~AUL FACOORY Address for Serv'ice: PATENT ATTORNEY SERVICES 26 Ellingworth P~arade Box 11ill Victoria 3)128 Australia Title: AIR FILTER HOLD)ER Associated Provisional Appl ications: No(s).: The following statemcnt is a full description of this invention, including the best method of perlborming it known to me/us:- Title: Air Filter Holder TECHNICAL FIELD The present invention relates to an air filter holder. More particularly the invention relates to an air filter holder for use in an air handling system providing heating, ventilating or air conditioning in a building.

BACKGROUND ART In recent times flexible ducting has become more widely used in air handling systems for providing heating, ventilation and air conditioning. This ducting has advantages for ease and •flexibility of installation and is very low cost. Since it is lightweight, the size of structural members to support the ducting and the other parts of the system can be reduced.

Other components of air handling systems, however, have remained relatively massive and S: more difficult and costly to install. One such component is the air filter, which is provided for cleaning the air current and removing particles mixed into the air flow. Typically flat or panel filters are placed over the inlet to the system and generally consist of a low packing density of coarse glass fibers held in a mesh cover. Bag type filters may also be employed in a similar manner. Both these arrangements, however, lack versatility and it may be necessary, for example, when using an in-line flat filter to provide a reducer in the ducting before the filter, thus requiring additional components and incurring higher installation costs.

Maintenance considerations in the mounting of the filter are also important, as the filter is liable to become clogged with collected particles and must be cleaned (or can be used on a throwaway basis). Typically flat filters have been mounted in relatively heavy and costly frameworks, such as channel sections, with which the flat filter may be slidingly engaged.

It will be understood that heretofore air filters for air handling systems have not achieved the most advantageous use of the properties of light weight, low cost and flexibility which are particularly advantageous when combined with the use of flexible ducting.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided an air filter holder for an air handling system, the holder including: a two-part body defining a passage between an air inlet and an air outlet; means for releasably connecting a first part and a second part of the two-part body, allowing access for the removal or insertion of a flat air filter; retaining means for removably retaining the flat air filter within the body, said retaining means including a mesh screen fixed to the first part which co-operates with an annular face of the second part to hold the edge of the filter therebetween, and wherein both the first and second parts include adaptor means for connection to at least two different size ducts.

In a preferred embodiment the first and second parts each include a screw thread to provide the releasable connection. Alternatively, a variety of other methods may be employed, such as captive fasteners, clamps etc.

Preferably the adaptor means include cylindrical portions for the connection to different size cylindrical ducts, the cylindrical portions being joined by frustroconical intermediate sections.

A varying number of cylindrical portions may be provided in different embodiments of the invention and they may be joined by any generally tapered section.

10 The part of the body in which the filter element is retained is preferably of a larger crosssection than the adjacent parts. Alternatively, pleated or extended surface filters having a greater surface area, may be used without requiring this larger cross-section area and allowing •the use of an increased packing density in the filter without a large drop in air flow rate.

15 It will be appreciated that while the present invention preferably uses mechanical filtration, it is also applicable to devices such as electrostatic precipitators or charged-media filters.

This invention provides a filter holder which is effective and efficient in operational use, which reduces maintenance costs, and which is modular in construction and versatile in operation. The device may be economically constructed and has an overall simple design which minimizes manufacturing costs and maximizes performance. The filter holder can be made from a smooth resinous material, providing improved acoustical control. This filter holder simplifies construction and maintenance of air handling systems by offering an essentially modular design which may be used either at an inlet or in an in-line position. The holder is sufficiently lightweight that it can be simply fitted to a standard connecting spigot on a ventilating fan for example, without requiring separate support.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 is a part sectional view of the a filter holder of the present invention; and Figure 2 is cross sectional view through plane AA of Fig. 1.

ooooo BEST MODES FOR CARRYING OUT THE INVENTION Referring to Figs. 1 and 2, a first preferred embodiment of the filter holder 100 of the present invention includes two axisymmetric components having hollow bodies enclosing a tapered 15 passage therethrough male adaptor 1 and female adaptor 2 (shown in a disconnected position in Fig.1).

The holder 100 locates a self-supporting disc-shaped filter cassette 3 in which filter material is held and which lies in a plane substantially perpendicular to air flow in direction D (and generally parallel to the common axis of the male and female adaptors 1, 2).

The female adaptor 2 includes a mesh screen 4 to support the filter cassette 3 and prevent it billowing. The screen 4 is releasably secured by means of lugs 7 on opposing sides of the female adaptor 2 which co-operate with a slot 8 in the screen 4. Aligning the lugs 7 and slots 8, the screen 4 is moved axially and rotated to secure it.

The male adaptor 1 has an external thread 5 which engages with the internal thread 6 on female adaptor 2 to secure the male and female adaptors 1, 2 and thereby fix the filter cassette 3. With the filter holder 100 assembled, the cassette 3 is held in position between the screen 4 and the annular end 9 of the male adaptor 1.

Both the male adaptor 1 and female adaptor 2 include tapered sections 30 comprising concentric cylindrical sections 10, 11, 12 joined by frustroconical intermediate sections 13, 10 14, with the smallest section 10 outermost. The sections 10, 11, 12 are adapted to receive three different diameters 150mm, 200mm and 250mm diameter) of ducting, thereby providing a means of readily adapting to varying duct sizes without the need for additional duct fittings. Optionally, different numbers and diameters of cylindrical sections 10, 11, 12 may be provided for additional versatility. On installation, when connecting ducting to the larger section 10, the sections 11 and 12 may optionally be cut off to reduce flow restriction.

.Q

The filter holder 100 is preferably moulded from plastic material but may alternatively be formed from sheet metal or other suitable material.

In operation, the filter holder 100 may be used at an inlet to a ducted air handling system, with air being drawn into the open end 40. Alternatively, when used at the inlet the male adaptor 1 may be removed and, for example a threaded collar (not shown) may be used to retain the cassette 3.

The filter holder 100 may be installed in an in-line configuration, wherein preferably flexible ducting (not shown) is used at the upstream end. Preferably the connection between the filter holder 100 and any component to which it is fixed incorporates sufficient rotational freedom or torsional flexibility to allow for relative rotation between the threaded male adaptor 1 and female adaptor 2, to permit the male adaptor 1 to be unscrewed from the female adaptor 2 for removal or insertion of the filter cassette 3.

The filter holder 100 may also be used in-line when connected to rigid ducting, provided that means are provided in the duct line, such as a telescoping section (not shown) ,to permit the 10 male adaptor 1 and female adaptor 2 to be separated.

.•o.oi Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

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Claims

1. An air filter holder for an air handling system, the holder including: a two-part body defining a passage between an air inlet and an air outlet; means for releasably connecting a first part and a second part of the two-part body, allowing access for the removal or insertion of a flat air filter; retaining means for removably retaining the flat air filter within the body, said retaining means including a mesh screen fixed to the first part which co-operates with an annular face of the second part to hold the edge of the filter therebetween, and wherein both the first and second parts include adaptor means for connection to at least two different size ducts. g*

2. The air filter holder of claim 1 wherein the first and second parts are releasably connected by a screw thread.

3. The air filter holder of claim 1 or claim 2 wherein the adaptor means include cylindrical portions for the connection to different size cylindrical ducts, the cylindrical portions being joined by frustroconical intermediate sections.

4. The air filter holder of any one of the preceding claims wherein the part of the body in which the filter element is retained is of a larger cross-section than the adjacent parts.

Air filtering apparatus for an air handling system, the apparatus including: a two-part body defining a passage between an air inlet and an air outlet; 7 a flat air filter; means for releasably connecting a first part and a second part of the two-part body, allowing access for the removal or insertion of the filter; retaining means for removably retaining the filter within the body, said retaining means including a mesh screen fixed to the first part which co-operates with an annular face of the second part to hold theedge of the filter therebetween, and wherein both the first and second parts include adaptor means for connection to at least two different size ducts.

6. The air filtering apparatus of claim 5 wherein the air filter is disc-shaped and aligned substantially perpendicular to the air flow, having a central axis coaxial with each of the said cylindrical sections.

7. An air filter holder substantially as hereinbefore described with reference to the accompanying drawings.

8. Air filtering apparatus substantially as hereinbefore described with reference to the accompanying drawings.