GB2412163A

GB2412163A - Controlling access to an opening

Info

Publication number: GB2412163A
Application number: GB0405942A
Authority: GB
Inventors: William Greenwood
Original assignee: GILBERTS
Current assignee: GILBERTS
Priority date: 2004-03-17
Filing date: 2004-03-17
Publication date: 2005-09-21
Anticipated expiration: 2024-03-17
Also published as: GB2412163B; GB0405942D0

Abstract

A blade 12 for controlling access to an opening has a first piece of material which defines at least a part of a first control surface 15 and at least a first part of an axle 14 via which the blade is pivotably mounted. The blade may be a component part of a fire damper for a ventilation duct of a building, the damper having for example four blades mounted within a housing 10. The first piece of material may also define a first part of a male element (52 fig 8) and a first part of a female element (64 fig 8), allowing adjacent blades to cooperate with one another to prevent or restrict the passage of smoke. The blade may include two identical blade halves (50 fig 8), which are made from steel in a pressing process and secured together by rivets or spot welding. The blades also include two rectangular tabs (84 fig 9) which are arranged to be deformed to secure each blade to a gear pinion 16 which is a component of the blade actuating mechanism.

Description

Controlling access to an opening This invention relates to controlling

access to an opening and particularly, although not exclusively, relates to dampers for controlling the flow of air or other gases through an opening. Preferred embodiments relate to fire dampers.

GB2151013A (Haslam) discloses a damper for a ventilation duct. The damper includes an array of damper blades each of which is mounted on a respective shaft provided with a pinion which engages a linearly movable toothed rack.

When smoke or a high temperature is detected, an electrical heating element heats wax in a cylinder to move a piston. The piston displaces a cylinder against the action of a spring so that a pin engaged in a spiral groove rotates a shaft. A pinion secured to the shaft displaces the rack thereby rotating each of the pinions to close the blades. Adjacent blades may move in the same or opposite directions.

One problem associated with the damper of GB2151013A is that it is relatively expensive to manufacture. For example, substantial time and materials are required to make the blades which incorporate a central shaft for example of steel rod.

It is an object of the present invention to address problems associated with controlling access to an opening.

According to a first aspect of the invention, there is provided an assembly comprising a housing having an opening and a blade which is pivotably mounted for controlling access through the opening, the blade comprising a first piece of material which defines: (i) at least a part of a first control surface for controlling access through the opening; and (ii) at least a first part of an axle via which the blade is pivotably mounted.

Thus, at least said part of said first control surface and lo said first part of said axle are unitary having been formed from a single piece of material, with no join being defined between said parts.

Said first piece of material is preferably sheet material which has been shaped to define said parts described.

Said first control surface preferably comprises a first major surface of the blade which is preferably arranged to be pivoted between a position wherein it substantially obturates part of the opening and a position wherein it does not substantially obturate said part of the opening.

Said first piece of material suitably defines at least 50%, preferably at last 75%, more preferably at least 90%, especially about 100% of the area of said first major surface of said blade. Thus, preferably said first major surface is defined substantially entirely by said first piece of material.

Said first piece of material preferably defines a first end part of at least part of an axle wherein said first end part is pivotably mounted for pivotably mounting the blade. For example, said first end part may be arranged within an opening in which it is pivotably mounted. Said first end part preferably has an arcuate, preferably a substantially semicircular cross-section.

Said first piece of material preferably defines a second end part of at least part of said axle, wherein said second end part is pivotably mounted for pivotably mounting the blade. For example, said second end part may be arranged within an opening (preferably opposite the opening in which the first end part is arranged) in which lo it is pivotably mounted. Said second end part preferably has an arcuate, preferably a substantially semi-circular cross-section.

The cross-sections of said first and second end parts are preferably substantially identical. Said first and second end parts are preferably a part of an elongate part of said blade. Said elongate part is preferably wholly defined by said one piece of material. Said elongate part preferably extends from one edge of the blade to an opposite edge thereof.

Preferably, said first piece of material defines at least a part of a male element, preferably along at least a part of an elongate edge of the blade. Said part of said male element is preferably curved, more preferably arcuate, in cross-section. Said part of said male element may curve through an angle of less than 180 and preferably greater than 90 , more preferably greater than 135 , especially greater than 160 . Said part of said male element suitably extends along at least 50%, preferably at least 75%, more preferably at least 90% of the length of the blade. Said part of said male element preferably extends from one edge of the blade to an opposite edge thereof.

Preferably, said first piece of material defines at least a part of a female element, preferably along at least a part of an elongate edge of the blade. Said female element preferably extends along an opposite elongate edge of the blade to that along which said male element extends. Said part of said female element suitably extends along at least 50%, preferably at least 75%, more preferably at least 90% of the length of the blade. Said lo part of said female element preferably extends from one edge of the blade to an opposite edge thereof.

Said first piece of material preferably defines securement means for securing the blade in position, for example in a position wherein it is substantially translationally fixed relative to said housing. Said securement means preferably comprises one or more deformable elements, for example tabs, which are parts of said first piece of material. Each said deformable element is suitably bent to a position in which it secures the blade in position.

Said securement means is preferably associated with said first part of said axle. Said securement means, for example deformable tab(s), is preferably provided at a free end of said first part of said axle.

In a preferred embodiment, said first piece of material is a single piece of material which defines: (i) at least a part of a first control surface of a blade; (ii) at least a first part of an axle of the blade; (iii) at least a first part of a male element of the blade; (iv) at least a first part of a female element of the blade; and (v) at least a first part of a securement means for securing the blade in position.

Said blade preferably comprises a second piece of material which defines: (i) at least a part of a second control surface for lo controlling access through the opening; and (ii) at least a second part of an axle via which the blade is pivotably mounted.

Said blade preferably comprises said first and second pieces of material which are secured together, wherein said respective parts of said first and second control surfaces together define the control surfaces (e.g. air deflection surfaces) of the blade (preferably opposite sides thereof); and said first and second parts of said axle together define an axle via which the blade is pivotably mounted.

Said part of said second control surface may have any feature of the part of said first control surface described. Preferably, said parts of said first and second control surfaces are substantially identical to one another.

Said second part of said axle may have any feature of the first part of the axle described. Preferably, said first and second parts of the axle are substantially identical to one another.

Said second piece of material preferably defines a second end part of at least part of said axle as described above for said first piece of material.

Said second piece of material preferably defines at least a part of a male element of the blade as described above for said first piece of material.

Said second piece of material preferably defines at least lo a part of a female element of the blade as described above for said first piece of material.

Said second piece of material preferably defines securement means as described above for said first piece of material.

Said first and second pieces of material are preferably substantially identical - that is, they are preferably shaped substantially identically.

Said first and second pieces of material are preferably secured together, for example by riveting (or the like), and together define: opposing control surfaces of the blade; respective axles at opposite ends of the blade by means of which the blade is pivotably mounted; and securement means at opposite ends of the blade for securing the blade in position. Preferably, said first and second pieces of material define a male element and a female element along opposite elongate edges of the blade.

Said first and second pieces of material preferably define a hollow axle via which the blade is pivotably mounted.

Preferably, the pieces of material define an axle having a hollow circular cross-section.

Each of said first and second pieces of material preferably include planar regions wherein planar regions of said first piece make face to face contact with planar regions of said second piece. Preferably, said first and second pieces are secured together by a securement means, for example a rivet (or the like), which extends between lo opposing planar regions.

Said assembly preferably includes a plurality of (preferably 3 to 10) blades as described above, wherein said blades preferably extend parallel to one another in an array. Preferably, when the blades include male and female elements as described, a male element of one blade is arranged to engage a female element of an adjacent blade when the blades are arranged in a closed position.

According to a second aspect of the invention, there is provided a method of forming a blade for controlling access to an opening, for example of an air flow passageway, the method comprising shaping a first piece of material so as to define: (1) at least a part of a first control surface of the blade for controlling access through an opening; and (ii) at least a first part of an axle via which the blade is arranged to be pivotably mounted.

Said first piece of material is preferably shaped to form a second part of an axle via which the blade is arranged to be pivotably mounted. Said first and second parts may be at opposite sides of the blade.

Said first piece of material is preferably shaped to form a part of a male element, preferably along at least a part of an elongate edge of the blade.

Said first piece of material is preferably shaped to form a part of a female element, preferably along at least a lo part of an elongate edge of the blade.

Said first piece of material is preferably shaped to form securement means for securing the blade in position, wherein said securement means may comprise tabs (or the like) which are arranged to be deformed in order to secure the blade in position.

Preferably, the method comprises shaping a second piece of material so as to define: (i) at least a part of a second control surface of the blade; and (ii) at least a second part of an axle via which the blade is arranged to be pivotably mounted.

The method may comprise securing the first and second shaped pieces of material together so that they together define opposing control surfaces of the blade and an axle.

The first and second pieces of material are preferably shaped to define axles at opposing ends of the blade.

The method preferably comprises contacting a planar part of the first shaped piece of material with a planar part of said second shaped piece of material and securing the first and second pieces of material together by a means which extends between the two planar parts.

The method preferably comprises selecting two identical shaped pieces of material and securing them together in superposed relationship.

According to a third aspect of the invention, there is lo provided a method of assembling a blade within a housing, the method comprising: (i) positioning an axle of the blade within an opening; and (ii) deforming a securement part of the blade to restrict translational movement of the axle within the opening.

Said securement part is preferably deformed by bending a part thereof, preferably through an angle of greater than 80 , to restrict said translational movement.

Said securement part is preferably a part of a first piece of material which is shaped to define: said first securement part; a part of a first control surface of the blade for controlling access through an opening; and at least a first part of an axle via which the blade is arranged to be pivotably mounted.

According to a fourth aspect of the invention, there is provided a blade as described herein per se.

The assembly, the blade and the methods relating thereto described according to the first, second, third and fourth aspects may be used in relation to any device which comprises an opening and a pivotably mounted blade.

Preferably, however, the device is an air flow damper and/or a fire damper. It may be arranged at the outlet end of an air flow passageway. The apparatus described may include means for causing pivotable movement of the blade or blades in dependence upon a condition sensed, for lo example the temperature sensed or the presence of smoke or other hazard.

Any feature of any aspect of any invention or embodiment described herein may be combined with any feature of any aspect of any other invention or embodiment described herein mutatis mutandis.

Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an exploded perspective view of a fire damper or duct damper with blades thereof in a "closed" position; Figure 2 is a perspective view of an assembled damper with blades thereof in a "closed" position; Figure 3 is a side elevation of the damper; Figure 4 is a detailed view of part circled IV in figure 3; Figure 5 is a front elevation of the damper in a closed position; Figure 6 is a top plan view of the damper; Figure 7 is a front elevation of a blade of the damper; Figure 8 is an end view of the blade (and an associated metal bush); and Figure 9 is an enlarged perspective view of the end of a blade.

Referring now to the drawings, a fire damper or duct damper which is adapted to be mounted in ventilation ducts or ventilation apertures in walls of buildings comprises a substantially rectangular housing 10 having four (or more) blades 12 extending transversely thereof. Each blade 12 comprises a shaft 14 and deflector vanes 15 diametrically arranged on opposite sides of the shaft 14. The shafts 14 are journalled at their ends in sides 17 of the housing 10 so that the blades 12 are pivotally movable relative to the housing 10 between a closed position (see Figure 1) and an open position in which the blades 12 extend parallel to the plane of the housing 10 and cooperate with one another to prevent or restrict the passage of smoke or noxious gases through the housing 10 and the ducting or aperture (not shown) in which the fire damper or duct damper is mounted.

A gear pinion 16 is secured on the portion of each shaft 14 which projects from one side of the housing 10 and the pinion 16 is provided with gear teeth on part of the circumference thereof which teeth mesh with the gear teeth of a rack 18 formed on a side of an associated elongate substantially rectangular aperture 20 in an operating member 22. The portion of the circumference of each gear pinion 16 which is provided with gear teeth is arranged to be sufficient to effect pivotal movement of the associated blade 12 between the open and closed position. The remaining portion of the circumference of each pinion 16 is a close fit with the other side of the aperture 20 to lo retain the gear teeth on the pinion 16 in engagement with the gear teeth of the rack 18. The operating member 22 is slidably mounted and is constrained to move linearly in a direction parallel to a plane containing the pivot axes of the blades 12.

The provision of racks 18 on opposite sides of adjacent apertures 20 results in movement of the operating member 22 producing rotation of adjacent blades 12 in opposite directions.

The operating member 22 cooperates with an operation device 30 which comprise a body 32 which is secured between opposing sides 34, 36 of the housing. The body supports a rotatably mounted shaft 38 (figure 1) which carries pinions 40 which are arranged to cooperate with racks 18 so that shaft 38 can be rotated to cause movement of operating member 22 and, in turn, movement of the blades.

The blades 12 are resiliently loaded towards their closed positions (i.e. figure 5 positions) by means (not shown).

For example a fusible link or other control device, is suitably provided for retaining the shaft 38 in a position to maintain the blades in an open position until circumstances necessitate the blades to assume their closed positions.

The configuration of blades 12 will now be described in detail with reference particularly to figures 1, 7 and 8.

The blades are substantially identical to one another.

Each is made up of two identical blade halves 50 which include a head 52, having an arcuate cross-section; an elongate planar neck 54 from which the head 52 projects; a first body part 56 which is stepped outwardly from the neck 54; a semi-circular second body part 58; a third body part 60 which is stepped outwardly from one end of leg 62; and an outwardly angled foot 64 extending from the other end of leg 62. The blade halves are made from steel (or any other suitable metal) in a pressing process.

The blade halves are arranged to be secured together in face to face contact by rivets or spot welds (or by the TOXILOCK (Trade Mark) mechanism) as represented by fixings 66 in figure 7. When so arranged, the blade halves define a blade having a substantially circular cross-section head with a narrow elongate gap 77 being defined between the opposed blade halves; a planar elongate neck 72; a hollow circular cross-section shaft 74 bounded on each side by hollow substantially rectangular cross-section regions 76; a planar elongate leg 80; and a downwardly open-channel 82.

As is clear from figure 9, each blade half also includes two rectangular tabs 84 at each end which are formed when the blades halves are pressed out. The tabs are arranged to be deformed to secure the blades to the gear pinions 16. In this regard, the gear pinions 16 include four arc- shaped slots 19 with respective pairs of slots being diametrically opposed. During assembly of the damper, the tabs 84 are pushed through the slots until an inwardly facing face of a pinion abuts transverse edge 88 of the blade. Then the tabs are bent at an angle of 90 and flattened so they lie flat against the outwardly facing face 90 of the pinion. As shown in figure 4, the tabs are lo bent alternatively inwardly (see tabs 84a) and outwardly (see tabs 84b). To facilitate smooth pivotal movement of the blades, a bush 89 is mounted at the ends of each shaft, the bush being arranged to seat within opening 91 in sides 17 of the housing.

The damper may operate as described generally in GB2151013A in that the blades may be pivoted to a closed position in certain situations. However, the blades are arranged to engage one another when in the closed position. In this regard, as the blades move to a closed position head 70 of one blade enters the channel 82 of the blade above, thereby locking the blades together along their extent. The provision of gap 77 at the highest point of head 70 affords to the blade a degree of tolerance, thereby facilitating engagement of heads 70 and channels 82. The engagement of heads 70 and channels 82 is effected between all adjacent blades so that a relatively rigid curtain is defined by the blades. In fire tests, it is found that the engagement of heads and channels restricts distortion of the curtain so that it remains intact (without openings being formed in it) for longer periods in comparison to dampers which have no such engagement.

To further limit the passage of air through the curtain defined by the blades, the heads 70 and/or channels 82 may incorporate sealing material, for example an intumescent sealing material.

It should be appreciated that the damper described herein may be relatively cheap and quick to manufacture. In fire and other appropriate tests it has been found to have lo excellent performance.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features

disclosed in this specification (including any

accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. An assembly comprising a housing having an opening and a blade which is pivotably mounted for controlling access through the opening, the blade comprising a first piece of material which defines: (i) at least a part of a first control surface for controlling access through the opening; and (ii) at least a first part of an axle via which the blade is pivotably mounted.

2. An assembly according to claim 1, wherein said first piece of material is sheet material which has been shaped to define said part of said first control surface and said first part of said axle.

3. An assembly according to claim 1 or claim 2, wherein said first control surface comprises a first major surface of the blade which is arranged to be pivoted between a position wherein it substantially obturates part of the opening and a position wherein it does not substantially obturate said part of the opening.

4. An assembly according to any preceding claim, wherein said first piece of material defines a first end part of at least part of an axle wherein said first end part is pivotably mounted for pivotably mounting the blade.

5. An assembly according to any preceding claim, wherein said first piece of material defines a second end part of at least part of said axle, wherein said second end part is pivotably mounted for pivotably mounting the blade.

6. An assembly according to claim 4 in combination with claim 5, wherein the cross-sections of said first and second end parts are substantially identical.

7. An assembly according to claim 6, wherein said first and second end parts are parts of an elongate part of said blade, wherein said elongate part is wholly defined by said one piece of material and said elongate part extends from one edge of the blade to an opposite edge thereof.

8. An assembly according to any preceding claim, wherein said first piece of material defines at least a part of a male element along at least a part of an elongate edge of the blade.

9. An assembly according to any preceding claim, wherein said first piece of material defines at least a part of a female element along at least a part of an elongate edge of the blade.

10. An assembly according to any preceding claim, wherein said first piece of material defines securement means for securing the blade in position, said securement means comprising one or more deformable elements being part(s) of said first piece of material.

11. An assembly according to any preceding claim, wherein said first piece of material is a single piece of material which defines: (i) at least a part of a first control surface of a blade; (ii) at least a first part of an axle of the blade; (iii) at least a first part of a male element of the blade; (iv) at least a first part of a female element of the blade; and (v) at least a first part of a securement means for securing the blade in position.

12. An assembly according to any preceding claim, wherein said blade comprises a second piece of material which defines: (i) at least a part of a second control surface for controlling access through the opening; and (ii) at least a second part of an axle via which the blade is pivotably mounted.

13. An assembly according to claim 12, wherein said blade comprises said first and second pieces of material which are secured together, wherein said respective parts of said first and second control surfaces together define the control surfaces of the blade; and said first and second parts of said axle together define an axle via which the blade is pivotably mounted.

14. An assembly according to claim 12 or claim 13, wherein said first and second pieces of material are shaped substantially identically.

15. An assembly according to any of claims 12 to 14, wherein said first and second pieces of material are secured together and together define: opposing control surfaces of the blade; respective axles at opposite ends of the blade by means of which the blade is pivotably mounted; and securement means at opposite ends of the blade for securing the blade in position.

16. An assembly according to any of claims 12 to 15, wherein said first and second pieces of material define a male element and a female element along opposite elongate edges of the blade.

17. An assembly according to any of claims 12 to 16, wherein said first and second pieces of material define a hollow axle via which the blade is pivotably mounted.

18. An assembly according to any of claims 12 to 17, wherein each of said first and second pieces of material include planar regions wherein planar regions of said first piece make face to face contact with planar regions of said second piece.

19. An assembly according to any preceding claim, wherein said assembly includes a plurality of blades, wherein said blades extend parallel to one another in an array.

20. An assembly according to claim 19, wherein a male element of one blade is arranged to engage a female element of an adjacent blade when the blades are arranged in a closed position.

21. A method of forming a blade for controlling access to an opening, for example of an air flow passageway, the method comprising shaping a first piece of material so as to define: (i) at least a part of a first control surface of the blade for controlling access through an opening; and (ii) at least a first part of an axle via which the blade is arranged to be pivotably mounted.

22. A method according to claim 21, wherein said first piece of material is shaped to form a second part of an axle via which the blade is arranged to be pivotably mounted.

23. A method according to claim 21 or claim 22, wherein said first piece of material is shaped to form a part of a male element.

24. A method according to any of claims 21 to 23, wherein said first piece of material is shaped to form a part of a female element.

25. A method according to any of claims 21 to 24, wherein said first piece of material is shaped to form securement means for securing the blade in position, wherein said securement means comprises tabs which are arranged to be deformed in order to secure the blade in position.

26. A method according to any of claims 21 to 25, the method comprising shaping a second piece of material so as to define: (i) at least a part of a second control surface of the blade; and (ii) at least a second part of an axle via which the blade is arranged to be pivotably mounted.

27. A method according to any of claims 21 to 26, the method comprising securing the first and second shaped pieces of material together so that they together define opposing control surfaces of the blade and an axle.

28. A method according to any of claims 21 to 27, the method comprising selecting two identical shaped pieces of material and securing them together in superposed relationship.

29. A method of assembling a blade within a housing, the method comprising: (i) positioning an axle of the blade within an opening; and (ii) deforming a securement part of the blade to restrict translational movement of the axle within the opening.

30. A method according to claim 29, wherein said securement part is deformed by bending a part thereof through an angle of greater than 80 , to restrict said translational movement.

31. A method according to claim 29 or claim 30, wherein said securement part is a part of a first piece of material which is shaped to define: said first securement parts a part of a first control surface of the blade for controlling access through an opening; and at least a first part of an axle via which the blade is arranged to be pivotably mounted.

32. A blade as described in any preceding claim per se.