Ventilation systems and components therefor

Abstract

A flexible connection (32) is described for forming a connecting passageway with coupling flange (20) or duct in a ventilation system. The flexible connection comprises a flexible sleeve (22) having an end for fitting over the coupling flange or duct. In one embodiment, a worm-drive clip (24) extends around the end of the sleeve to secure the end of the sleeve to the coupling flange or duct. The clip extends through a tunnel (38) formed partly around the end of the sleeve to hold the clip in position around the sleeve before the end of the sleeve is secured to the coupling flange or duct. In another embodiment, the flexible sleeve is permanently bonded to the coupling flange. A component (94) is also described for use with a ventilation unit having an airway and an array of securing means around the airway. The component has an aperture for alignment with the airway, and an array (78) of holes (76) around the aperture for alignment with the securing means so that the component can be secured to the ventilation unit. The component also has at least one anti-vibration mount (30) for securing the component to a support structure. Additionally or alternatively, the component is alternatively for use with a second ventilation unit having an airway and a different array of securing means around the airway. In this case, the component has a second array (80) of holes for alignment with the securing means of the second ventilation unit so that the component can alternatively be secured to the second ventilation unit.

Description

DESCRIPTION

This invention relates to ventilation systems and components therefor.

In particular, a first aspect of the invention relates to a flexible connection for forming a connecting passageway with a coupling flange or duct in a ventilation system, the flexible connection comprising a flexible sleeve having an end for fitting over the coupling flange or duct, and a worm-drive clip for extending around the end of the sleeve to secure the end of the sleeve to the coupling flange or duct. Such flexible connections are used to reduce the amount of vibration that is transmitted around the ventilation system. During fitting, the appropriate size of worm-drive clip needs to be selected, the end of the sleeve needs to be placed in its proper position around the coupling flange or duct, the worm-drive clip needs to be placed in its proper position around the end of the sleeve, and then the worm-drive clip needs to be tightened while maintaining the proper positions of the sleeve and clip. Typically, the diameter of the duct or coupling flange may be between 250 mm and 1,000 mm. Especially with the larger sizes, it will be appreciated that fitting the worm-drive clip in the correct position around the flexible sleeve is difficult.

The first aspect of the invention is concerned with providing a solution to this problem.

The flexible connection of the first aspect of the invention is characterised in that the clip extends through a tunnel formed partly around the end of the sleeve to hold the clip in position around the sleeve before the end of the sleeve is secured to the coupling flange or duct.

It will therefore be appreciated that, during fitting, when the flexible connection is properly positioned on the coupling flange or duct, the worm-drive clip is also properly positioned automatically, and it is merely necessary to maintain that position of the sleeve on the coupling flange or duct while tightening the worm-drive clip. It should also be noted that if the flexible connection is supplied with the worm-drive clip already fitted into the channel, the appropriate sized clip will always be used, and there is no risk of mislaying the clip.

Preferably, the tunnel is conveniently formed by a turned-back hem at the end of the sleeve. Preferably, the tunnel extends completely around the end of the sleeve, except in the region of the worm screw of the clip, which generally will be only a small proportion of the circumference of the sleeve.

Preferably, the sleeve is formed from a panel of material that is seamed lengthwise of the sleeve with an overlapping seam, the worm screw of the clip being disposed in the region of the overlapping seam. The overlapping seam will tend to provide a tougher portion of the sleeve, and so the worm screw of the clip will therefore bear on the tougher portion.

The other end of the sleeve may be arranged to fit over a further coupling flange or duct in the ventilation system, said other end of the sleeve also having such a worm-drive clip extending through such a tunnel at said other end of the sleeve, so that the advantages of this aspect of the invention are provided at both ends of the sleeve.

A second aspect of the invention is concerned with providing another solution to the problem mentioned above.

In accordance with the second aspect of the invention, there is provided a coupling assembly for forming a connecting passageway with a ventilation unit, the coupling assembly comprising a coupling flange arranged to be secured to the ventilation unit, and a flexible sleeve permanently bonded to the coupling flange.

Such flexible sleeves are normally always used with a coupling flange at least at one end of the sleeve. Therefore, by supplying a flexible sleeve permanently bonded to a coupling flange, it becomes completely unnecessary to assemble the sleeve with the coupling flange, at least at one end of the sleeve, during installation of a system.

A number of components are typically used in a ventilation system that have an aperture for alignment with an airway of a ventilation unit, and an array of holes around the aperture for alignment with corresponding securing means (such as bolt holes or captive nuts) on the ventilation unit so that the component can be secured to the ventilation unit. Examples of such components are coupling flanges and fan guards, and examples of such ventilation units are fan units and acoustic attenuators. It is also conventional to mount such ventilation units on mounting feet. Each mounting foot has one of two anti-vibration mounts for securing to a support structure, such as a floor or ceiling hanger. Typically, the mounting foot has two or three holes corresponding to the securing means on the ventilation unit by which it is bolted to the ventilation unit. It will therefore be appreciated that, in a position where such a component is to be fitted to a ventilation unit and a mounting foot is also to be provided, the three parts need to be properly aligned while the securing means are fitted, and this can cause problems, especially with large or heavy ventilation units.

A third aspect of the invention is concerned with providing a solution to this problem.

In accordance with the third aspect of the invention, there is provided a component for use with a ventilation unit having an airway and an array of securing means around the airway, the component having an aperture for alignment with the airway, an array of holes around the aperture for alignment with the securing means so that the component can be secured to the ventilation unit, and at least one anti-vibration mount for securing the component to a support structure.

In other words, the known component and mounting foot are combined, which facilitates installation.

A fourth aspect of the invention relates in particular to a component for use with a ventilation unit having an airway and an array (usually a regular array) of securing means around the airway, the component having an array of holes for alignment with the securing means so that the component can be secured to the ventilation unit.

As will be described in more detail below, for systems available in the United Kingdom, there has been some standardisation of the arrays that are used. However, there remain two different standards for fans units with a nominal airway diameter of 400 mm or larger. It is therefore necessary to use a component of the appropriate standard. Not having a single standard causes problems with manufacturing, stocking, ordering, fitting and replacement.

The fourth aspect of the invention is concerned with providing a solution to these problems.

The component of the fourth aspect of the invention is characterised in that it is alternatively for use with a second ventilation unit having an airway and a different array of securing means around the airway, the component having a second array of holes for alignment with the securing means of the second ventilation unit so that the component can alternatively be secured to the second ventilation unit.

A single component can therefore be used with both standards.

The holes of the first-mentioned array may have a different diameter to the holes of the second array. Additionally or alternatively, the holes of the first array may lie on a pitch circle having a different diameter to a pitch circle on which the holes of the second array lie. Additionally or alternatively, the first and second arrays may have different numbers of holes.

The component may, for example, be an acoustic attenuator, a mounting foot and/or a coupling flange, or a fan guard.

It will be appreciated that the features of any two or more of the above-mentioned four aspects of the invention may be employed in a single component.

Specific embodiments of the present invention will now be described, purely by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic diagram of part of a ventilation system;

FIG. 2 is a side view, on a larger scale, of a flexible coupling and coupling flange that may be used in the system of FIG. 1;

FIG. 3 is a sectioned view of part of FIG. 2, taken along the section line 3-3;

FIG. 4 is an end view, on a larger scale, of part of the flexible coupling of FIG. 2;

FIG. 5 is similar to FIG. 3, but showing a modification;

FIG. 6 is an end view of an attenuator that may be used in the system of FIG. 1;

FIG. 7 is a face view of an inlet guard that may be used in the system of FIG. 1;

FIG. 8 is a face view of a coupling flange that may be used in the system of FIG. 1;

FIG. 9 is a side view of the coupling flange of FIG. 8;

FIG. 10 is a front view of a mounting foot that may be used in the system of FIG. 1;

FIG. 11 is a side view of the mounting foot of FIG. 10;

FIG. 12 is a face view of a combined mounting foot and coupling flange that may be used in the system of FIG. 1;

FIG. 13 is a side view of the combined mounting foot and coupling flange of FIG. 12;

FIG. 14 is a face view of a combined mounting foot and inlet guard that may be used in the system of FIG. 1; and

FIG. 15 is a side view of the combined mounting foot and inlet guard of FIG. 14.

Referring to FIG. 1, a part of a ventilation system comprises a generally cylindrical fan unit 10, a generally cylindrical sound attenuator 12 and a duct 14 coupled in sequence for feeding air to a building. Each end of the fan unit 10 has a radially outwardly projecting flange 16 formed with an array of fixing holes. An inlet guard 18 with complementary fixing holes is secured to the inlet side (to the right in the drawing) of the fan unit 10 with nuts and bolts. Each end of the attenuator 12 has an annular face with a complementary array of captive nuts. The left end of the attenuator 12 is secured to the right end of the fan unit 10 with bolts that pass through the holes in the flange 16 into the captive nuts. The right end of the attenuator 12 is secured by bolts to a coupling flange 20 having a radially outwardly projecting flange formed with a complementary array of fixing holes. The coupling flange 20 also has a cylindrical flange of similar diameter to the duct 14, and a flexible sleeve 22 has its ends fitted over the cylindrical flange and the duct 14 and secured thereto using worm drive clips 24. The fan unit 10 and attenuator 12 are supported on the floor 26 by three mounting feet 28 each on a pair of anti-vibration mounts 30. Each mounting foot 28 is formed by a bent piece of plate that is attached to the fan unit 10 or attenuator 12 by two or three of the bolts previously described. The anti-vibration mounts 30 reduce the vibration that is transmitted to the floor 26, and the flexible sleeve 22 reduces the vibration that is transmitted to the duct 14.

The arrangement insofar as it is described in the previous paragraph is conventional, and a number of improvements to the known arrangement will now be described.

The nominal diameter of the duct 14 and the airway through the fan unit 10 and attenuator 12 may typically be between 250 mm and 1,000 mm. Especially with the larger sizes, it will be appreciated that fitting the worm-drive clips 24 in the correct positions around the flexible sleeve 22 is difficult. To deal with this problem, a flexible connection 32 as shown in FIGS. 2 to 4 may be employed. The flexible connection 32 comprises a sleeve 22 formed from a panel of flexible reinforced plastics material that is about 1.5 mm thick. The panel is seamed lengthwise with stitching 34 to form an overlapping seam 36 that will be tougher than the remainder of the sleeve 22. At each end of the sleeve 22, a channel 38 is formed by a turned-back hem that is stitched at 40. Before forming each channel 38, the ends of the sleeve 22 are cut back in the region of the overlapping seam 36 so that the channels are not formed in that region. The worm-drive clips 24 are threaded through the channels 38 so that the worm screw 42 of each clip is positioned in the region of the overlapping seam 36. It will therefore be appreciated that, during fitting, when the flexible connection 32 is properly positioned on the cylindrical flange 44 of the coupling flange 20 or on duct 14, the worm-drive clips 24 are also properly positioned automatically, and it is merely necessary to maintain that position while tightening the worm-drive clips 24. It should also be noted that if the flexible connection 32 is supplied with the worm-drive clips 24 already fitted into the channels 38, the appropriate sized clips 24 will always be used, and there is no risk of mislaying the clips 24. It will also be appreciated that the worm screws 42 will always bear upon the tougher portion of the sleeve 22 in the region of the overlapping seam 36.

FIG. 5 illustrates another way of dealing with the problems described above with the conventional flexible sleeve 22. In this case, the right end of the sleeve 22 is permanently bonded to the cylindrical flange 44 of the coupling flange 20, for example using an epoxy resin or silicone adhesive 46. The left end of the sleeve 22 may be provided with a channel 38 as described above with reference to FIGS. 2 to 4, or alternatively may be secured to the duct 14 in the conventional way.

As mentioned previously, the fan unit 10, attenuator 12 and other components are secured together by circular arrays of bolts. For systems available in the United Kingdom, there has been some standardisation of the arrays that are used. However, there remain two different standards for fans units with a nominal airway diameter of 400 mm or larger, that will be referred to in this specification as “Pattern A” and “Pattern B.” Fan units that employ Pattern A include: Woods JM range; Vent-Axia (up to and including 630 mm diameter); Roof Units Europitch; Roof Units Eurofoil; Elta (long and short case); and Nuaire. Fan units that employ Pattern B include: Helios; Vent-Axia (over 630 mm diameter); EBM Zeihl; and Elta (compact). The parameters of these patterns for various sizes of fan unit are set out in the following table:

	No. of Holes./
	Angular Pitch		Bolt Size (metric)
Airway	Pattern	Pattern	Pitch Circle Diameter	Pattern	Pattern
Diameter	A	B	Pattern A	Pattern B	A	B
250 mm	8 off/45°	286 mm	M6
315 mm		355 mm	M8
355 mm		395 mm
400 mm	8 off/	12 off/	450 mm	438 mm	M10	M8
450 mm	45°	30°	500 mm	487 mm
500 mm	12 off/		560 mm	541 mm
560 mm	30°	16 off/	620 mm	605 mm
630 mm		22½°	690 mm	674 mm		M10
710 mm	16 off/		770 mm	751 mm
800 mm	22½°	24 off/	860 mm	837 mm
900 mm		15°	970 mm	934 mm	M12
1,000 mm			1,070 mm	1,043 mm

Accordingly, when a Pattern A fan unit 10 is used, it is also necessary to use the appropriate size of Pattern A attenuator 12, Pattern A flange coupling 20, Pattern A inlet guard 18 and Pattern A mounting feet 28, and the appropriate number and size of nuts and bolts to secure the assembly together. Not having a single standard for the fan units 10 therefore causes problems with manufacturing, stocking, ordering, fitting and replacement. Way of dealing with this problem will now be described.

FIG. 6 shows a sound attenuator 12 for an 800 mm diameter system. The attenuator 12 has an annular, acoustically-damping casing 48 with a nominal internal diameter of 800 mm and a central, acoustically damping pod 50 supported in the casing 48 by three radial arms 52. Each end face 54 of the attenuator is fitted with captive nuts 56 to receive the securing bolts. Rather than the nuts 56 being arranged in a single array for Pattern A or Pattern B in the conventional manner, the nuts 56 are arranged in two arrays for both Pattern A and Pattern B so that the attenuator 12 can be used with fan units 10 having either pattern. Accordingly, sixteen M10 captive nuts 56 with an angular pitch of 22½° lie on a pitch circle 58 having a diameter of 860 mm to form Pattern A, and twenty-four M10 captive nuts 56 with a smaller angular pitch of 15° lie on a pitch circle 60 having a smaller diameter of 837 mm to form Pattern B. The nuts 56 on the two pitch circles 58,60 are symmetrically staggered so that no two nuts 56 lie on the same radius.

FIG. 7 shows an inlet guard 18 for a 560 mm diameter system. The guard 18 comprises an annular plate 62 with a nominal internal diameter of 560 mm and a central, wire-mesh disc 64. The plate 62 has through holes 66 to receive the securing bolts. Rather than the holes 66 being arranged in a single array for Pattern A or Pattern B in the conventional manner, the holes 66 are arranged in two arrays for both Pattern A and Pattern B so that inlet guard 18 can be used with fan units 10 having either pattern. Accordingly, twelve 10 mm clearance holes 66 with an angular pitch of 30° lie on a pitch circle 68 having a diameter of 620 mm to form Pattern A, and sixteen smaller 8 mm clearance holes 66 with a smaller angular pitch of 22½° lie on a pitch circle 70 having a smaller diameter of 605 mm to form Pattern B. The holes 66 on the two pitch circles 68,70 are symmetrically staggered so that no two holes 66 lie on the same radius.

FIGS. 8 and 9 show a flange coupling 20 for a 500 mm diameter system. The flange coupling 20 comprises an annular plate 72 with a nominal internal diameter of 500 mm and a cylindrical flange 44 also with a nominal diameter of 500 mm. The plate 72 has through holes 74 to receive the securing bolts. Rather than the holes 74 being arranged in a single array for Pattern A or Pattern B in the conventional manner, the holes 76 are arranged in two arrays for both Pattern A and Pattern B so that flange coupling 20 can be used with systems having either pattern. Accordingly, twelve 10 mm clearance holes 76 with an angular pitch of 30° lie on a pitch circle 78 having a diameter of 560 mm to form Pattern A, and twelve smaller 8 mm clearance holes 76 with an angular pitch of 30° lie on a smaller pitch circle 80 having a diameter of 541 mm to form Pattern B. The holes 76 on the two pitch circles 78,80 are symmetrically staggered so that no two holes 76 lie on the same radius.

FIGS. 10 and 11 show a mounting foot 28 for a 500 mm diameter system. The mounting foot 28 comprises a plate that is folded through a right angle to form a vertical portion 82 and a horizontal portion 84. A pair of the anti-vibration mounts 30 are secured beneath the horizontal portion 84. The upper edge 86 of the vertical portion 82 is arcuate having a nominal radius of curvature of half the system diameter, i.e. 250 mm. The vertical portion 82 also has through holes 88 to receive the securing bolts. A conventional mounting plate would have two or three such holes 88 formed on a pitch circle, concentric with the arcuate upper edge 86, of the appropriate diameter for Pattern A or Pattern B. However, the vertical portion 82 of the mounting foot 28 has two arrays for both Pattern A and Pattern B so that mounting foot can be used with systems having either pattern. Accordingly, two 10 mm clearance holes 88 with an angular pitch of 30° lie on a pitch circle 90 having a diameter of 560 mm to form Pattern A, and three smaller 8 mm clearance holes 88 with an angular pitch of 30° lie on a smaller pitch circle 92 having a diameter of 541 mm to form Pattern B. The holes 88 on the two pitch circles 90,92 are symmetrically staggered so that no two holes 88 lie on the same radius.

FIGS. 12 and 13 show a mounting bracket 94 that may be used in the system of FIG. 1 in place of the separate coupling flange 20 and mounting foot 28 to the left of the attenuator 2. The mounting bracket 94 is formed by producing the annular plate 72 of FIGS. 8 and 9 integrally from the same sheet of metal as the mounting foot 28 of FIGS. 10 and 11. It will therefore be appreciated that the installation of the mounting bracket 94 is simpler and quicker than the installation of the separate coupling flange 20 and mounting foot 28, and that the mounting plate 94 may be used with Pattern A or Pattern B systems.

FIGS. 14 and 15 show a mounting bracket 96 that may be used in the system of FIG. 1 in place of the separate inlet guard 18 and mounting foot 28 to the right of the fan unit 10. The mounting bracket 96 is formed by producing the annular plate 62 of FIG. 7 integrally from the same sheet of metal as the mounting foot 28 of FIGS. 10 and 11. It will therefore be appreciated that the installation of the mounting bracket 96 is simpler and quicker than the installation of the inlet guard and mounting foot 28, and that the mounting plate 96 may be used with Pattern A or Pattern B systems.

It should be appreciated that many modifications and development s may be made to the embodiments of the invention described above.

For example, although an airflow passageway with a circular cross-section has been described, the invention is also applicable in the case of airflow passageways with non-circular, for example square or rectangular, airflow passageways.

Also, an arrangement has been described for mounting the ventilation units on a floor, the invention is also applicable to arrangements that are suspended, for example from a ceiling or roof.

It should be noted that the embodiments of the invention have been described above purely by way of example and that many other modifications and developments may be made thereto within the scope of the present invention.

Claims

1. A component (94;96) for use with a ventilation unit (10;12) having an airway and an array of securing means around the airway, the component having an aperture for alignment with the airway, an array (78) of holes (76) around the aperture for alignment with the securing means so that the component can be secured to the ventilation unit, and at least one anti-vibration mount (30) for securing the component to a support structure:

2. A component as claimed in claim 1, wherein the component is alternatively for use with a second ventilation unit having an airway and a different array of securing means around the airway, the component having a second array (80) of holes (76) for alignment with the securing means of the second ventilation unit so that the component can alternatively be secured to the second ventilation unit.

3. A component (12;20;28;94;96) for use with a ventilation unit (10) having an airway and an array of securing means around the airway, the component having an array (58;68;78;90) of holes (56;66;76;88) for alignment with the securing means so that the component can be secured to the ventilation unit, characterised in that the component is alternatively for use with a second ventilation unit having an airway and a different array of securing means around the airway, the component having a second array (60;70;80;92) of holes (56;66;76;88) for alignment with the securing means of the second ventilation unit so that the component can alternatively be secured to the second ventilation unit.

4. A component as claimed in claim 3, wherein the holes of the first-mentioned array have a different diameter to the holes of the second array.

5. A component as claimed in claim 3, wherein the holes of the first array lie on a pitch circle (58;68;78;90) having a different diameter to a pitch circle (60;70;80;92) on which the holes of the second array lie.

6. A component as claimed in claim 3, wherein the first and second arrays have different numbers of holes.

7. A component as claimed in claim 3, wherein each array is regular.

8. A component as claimed in claim 3, wherein the component is an acoustic attenuator (12).

9. A component as claimed in claim 3, wherein the component is one of: a mounting foot (28;94;96); a fan guard (18;96); and a coupling flange (20;94).

10. A component as claimed in claim 1, wherein the component is one of: a fan guard (96); and a coupling flange (94).

11. A component as claimed in claim 1, wherein the component is a coupling flange (94) having a flexible sleeve (22) permanently bonded (at 46) to the coupling flange.

12. A component as claimed in claim 3, wherein the component is a coupling flange (20;94) having a flexible sleeve (22) permanently bonded (at 46) to the coupling flange.

13. A coupling assembly for forming a connecting passageway with a ventilation unit (10;12), the coupling assembly comprising a coupling flange (20) arranged to be secured to the ventilation unit, and a flexible sleeve (22) permanently bonded (at 46) to the coupling flange.

14. A flexible connection (32) for forming a connecting passageway with a coupling flange (20;94) or duct (14) in a ventilation system, the flexible connection comprising a flexible sleeve (22) having an end for fitting over the coupling flange or duct, and a worm-drive clip (24) for extending around the end of the sleeve to secure the end of the sleeve to the coupling flange or duct, characterised in that the clip extends through a tunnel (38) formed partly around the end of the sleeve to hold the clip in position around the sleeve before the end of the sleeve is secured to the coupling flange or duct.

15. A flexible connection as claimed in claim 14, wherein the tunnel is formed by a turned-back hem at the end of the sleeve.

16. A flexible connection as claimed in claim 14, wherein the tunnel extends completely around the end of the sleeve, except in the region of the worm screw of the clip.

17. A flexible connection as claimed in claim 14, wherein the sleeve is formed from a panel of material that is seamed lengthwise of the sleeve with an overlapping seam (36), the worm screw (42) of the clip being disposed in the region of the overlapping seam.

18. A flexible connection as claimed in claim 14, wherein the other end of the sleeve is arranged to fit over a further coupling flange (20;94) or duct (14) in the ventilation system, said other end of the sleeve also having such a worm-drive clip (24) extending through such a tunnel (38) at said other end of the sleeve.

19. A flexible connection as claimed in claim 14, in combination with a coupling flange (94) for use with a ventilation unit (10;12) having an airway and an array of securing means around the airway, the coupling flange having an aperture for alignment with the airway, an array (78) of holes (76) around the aperture for alignment with the securing means so that the coupling flange can be secured to the ventilation unit, and at least one anti-vibration mount (30) for securing the coupling flange to a support structure.

20. A component as claimed in claim 1, in combination with at least one such ventilation unit.

21. A component as claimed in claim 3, in combination with at least one such ventilation unit.

22. A coupling assembly as claimed in claim 13, in combination with at least one such ventilation unit.

23. A flexible connection as claimed in claim 14, in combination with at least one such ventilation unit.

24. A flexible connection as claimed in claim 14, in combination with a coupling flange (20;94) for use with a ventilation unit (10) having an airway and an array of securing means around the airway, the coupling flange having an array (58;68;78;90) of holes (56;66;76;88) for alignment with the securing means so that the coupling flange can be secured to the ventilation unit, wherein the coupling flange is alternatively for use with a second ventilation unit having an airway and a different array of securing means around the airway, the coupling flange having a second array (60;70;80;92) of holes (56;66;76;88) for alignment with the securing means of the second ventilation unit so that the coupling flange can alternatively be secured to the second ventilation unit.