GB2167529A

GB2167529A - Duct valve

Info

Publication number: GB2167529A
Application number: GB08429551A
Authority: GB
Inventors: Derek Barker
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-11-22
Filing date: 1984-11-22
Publication date: 1986-05-29
Also published as: GB8429551D0

Abstract

A duct valve assembly, for ventilating, air conditioning, heating and refrigeration, comprising a valve body housing a rotatable valve plate 20 across the internal passage section thereof, one or more spaced valve spindles 22 with one or more surface locating portions for an operating arm, the valve plate having a shape generally corresponding to the duct cross-section locally and selectively movable to an open position aligned with or parallel to the duct axis and a closed position transverse thereto, one or more flexible free-moving bearing and seal elements 27 incorporating apertures (30) of complementary shape to a corresponding cross-sectional portion of said spindles, the bearings thereby being captive and rotatable in conjunction with the respective valve spindles whilst maintaining sealing engagement with the duct wall through sealing flanges 28, 29. <IMAGE>

Description

SPECIFICATION Duct valve This invention relates to a duct valve, and is particularly but not exclusively, concerned with a valve for an air duct of a ventilating system, which embraces air-conditioning, heating and refrigeration systems employing a con rolled flow of air under controlled conditions of temperature and humidity and flow rate through a duct.

Regulation of air flow is typically by means of a flap valve of shape corresponding to the duct cross-section, allowing for obstruction or closure of the duct cross-section by the plate when disposed transverse thereto or at some inclination to the duct axis in order to engage the valve plate edges with the internal duct wall.

Such a plate or flap valve is generally rotated or pivoted from an open to a closed position about a pivot axis defined by a valve spindle or one or more mutually aligned valve spindle portions, which are mounted in bearings in the duct wall.

One end of at least one of the spindles is secured to an operating arm or lever for rotation of the valve plate about the valve spindles.

Even such a straightforward mechanical arrangement requires fairly elaborate machining of separate components. In particular, the valve spindle must have a circular section locally where it passes through the spindle bearing in the duct wall and one or more flats at an outer end portion to locate the operating arm and again flat or slots at the other end to mount the valve plate. Thus the spindle itself requires elaborate laborious machining.

Adjustment of the valve plate position and the valve operating lever may be effected by the connection between the operating lever and the valve spindle. In particular, the lever conveniently has a clamping arrangement on the valve spindle, typically using a bolted wing nut operating in a quadrant slot of a quadrant shaped extension to the lever or a quadrant shaped slot in a quadrant shaped plate secured to the pipe. Such an arrangement is typically referred to as a "Damper Quadrant Control".

With such a conventional arrangement further complications arise with the bearing itself, particularly for the circular duct cross-sections.

The present invention is concerned with obviating the need for specially machined spindles and fabricated bearings.

According to one aspect of the invention there is provided a duct valve comprising a valve plate mounted on the one or more valve spindles which are received in a rotatable resilient bearing seal with an aperture of complementary shape to the spindle locally whereby rotation of the valve plate and valve spindle is accommodated by movement of the bearing which is also provided with a peripheral seal for sealingly engaging and supporting the spindle with respect to the duct wall.

Such a flexible bearing seal accommodates irregularities in size and shape of the spindle and duct and valve plate whilst retaining free movement of the valve and ensuring sealing at the pivot point of the valve plate with respect to the duct walls. Fabrication, installation, replacement and maintenance are also facilitated.

In particular, it is only necessary to have a uniform section valve spindle, for example a convenient rectangular section which is received in the corresponding rectangular slot in the bearing and with which the valve plate can readily abut in face to face relationship to facilitate mounting by clamping.

The rectangular section of spindle is also the correct shape for mounting and locating the operating lever or quadrant for driving engagement therewith.

The bearing seal as a whole rotates with the spindle and seals against the duct walls by spaced locating flanges on either side of a recess or groove about the periphery of the bearing itself, which may take the form of an annular or cylindrical ring.

There now follows a description of the particular embodiment to the invention, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a conventional duct valve arrangement for a circular duct or pipe; Figure 2 shows a conventional twin-valve plate arrangement for a rectangular duct; Figure 3 shows a conventional valve plate spindle; Figure 4 shows a conventional valve spindle bearing for the duct wall; Figure 5 shows a duct valve according to the invention; Figure 6 shows a detail sectional view of the mounting of the valve spindle of valve according to Figure 5; Figure 7 shows a duct valve spindle according to the invention; and Figure 8 shows a duct valve bearing seal according to the invention.

Referring to the drawings, a conventional duct valve comprises one or more valve plates (10) mounted in a duct (11) and whose individual or combined plate cross-section when disposed generally transverse to the duct axis (13) generally corresponds to the duct cross-section locally, in order to obstruct or impede flow through the duct.

The or each valve plate (10) is pivoted abouts its axis (12) generally transverse to the duct axis (13) in order to allow the plate to move from a position generally aligned with the duct axis (13), and in which the valve is open and the resistance to flow through the duct is at a minimum, and a closed position in which the valve plate (10) is generally transverse to the duct axis (13).

The valve plate (10) is mounted upon one or more aligned valve spindles (14), such as shown in Figure 3 where the valve spindle (14) is of rectangular section at one end, with spaced transverse holes (15) for mounting a valve plate (10), a cylindrical intermediate section (16) for reception in a support bearing (18), shown in Figure 4 and a square-section end portion (17) for locating an (un shown) operating arm or quadrant. It will be appreciated that this valve spindle itself requires elaborate machining and is complicated and costly to manufacture as well as being intricate to assemble.

The valve spindle is mounted at one end in a bearing (18) shown in Figure 4 and which has a circular bore to receive the cylindrical portion (16) of the valve spindle and a mounting flange (19) to engage the duct wall (11), with suitable fastending means e.g. bolts.

Particularly for a circular duct the bearing (18) is thus another specially cast and machined part.

In contrast to the foregoing conventional arrangement, the present invention, as described with reference to Figures 5 to 8, is somewhat simpler and easier to fabricate and assemble.

Referring to Figures 5 through 8, a duct valve according to the invention comprises a valve plate (20) mounted on spaced mutually aligned valve spindles (22) along a diameter thereat and received in combined bearing and seals (27), shown in more detail in Figure 8.

Each spindle, shown in more detail in Figure 7 comprises a uniform rectangular section rod with spaced transverse mounting bores (25) for receiving clamping screws for securing the spindle to the valve plate (20). The rectangular section of the valve spindle is received in a corresponding rectangular slot (30) in a valve spindle bearing (27), which comprises a resiliently deformable cylindrical or annular member with a peripheral recessor groove (29) defining spaced sealing flanges (28) for embracing the duct wall thickness, as shown in Figure 6, to allow the bearing to rotate in sealing engagement with duct walls and in conjunction with the valve spindle itself. In this way the valve spindles and the valve itself are supported, located and sealed in position in the duct whilst retaining freedom of movement of the valve for rotation between the open and closed positions.

It will be appreciated that other valve spindle cross sections can be employed, for example polygonal or cylindrical section with a flat, and that the rotary seal may be achieved between the valve spindle and the bearing aperture with the bearing held captive or even also rotatable in the duct walls I although for simplicity a valve spindle of uniform section has advantages and as this armsection must be compatible with both the valve plate and the operating arm, a non-circular shape is advantageous.

In order to avoid the valve seal periphery being cut or worn by the duct wall aperture edges some buffering or cushioning or flanging of the duct wall aperture to receive the bearing may be provided.

However, such valves are not necessarily in continuous use and thus the rate of wear may not be great, in which case such additional provision may not be necessary.

The present invention is particularly applicable to air ducts, but may be used on other pipe applications.

Claims

1. A duct valve assembly comprising a valve body housing a movable valve plate across the internal passage section thereof, one or more spaced valve spindles with one or more surface locating portions for an operating arm, a valve plate of shape generally corresponding to the duct crosssection locally and selectively movable to an open position aligned with or parallel to the duct axis and a closed position transverse thereto, one or more flexible free-moving bearing and seal elements incorporating apertures of complementary shape to a corresponding cross- sectional portion of said spindles, the bearings thereby being captive and movable or rotatable in conjunction with the respective valve spindles whilst maintaining sealing engagement with the duct wall.

2. A valve assembly as claimed in Claim 1, wherein said bearings comprise annular portions of synthetic plastics or rubber material with a peripheral recess or groove with spaced flanges embracing the duct [cylindrical] walls and in sealing engagement therewith and with the spindle.

3. A valve assembly as claimed in Claim 1 or Claim 2, wherein said valve spindle is of uniform, for example rectangular section.

4. A valve assembly as claimed in any of the preceeding Claims, comprising a heating or airconditioning air duct valve assembly, wherein said valve plate comprises a circular plate with spaced valve spindle rods secured thereto at diametrically opposite positions and slotted or recessed to receive the edge thickness thereof and rectangular at least at their remote outer ends and received in apertures in spaced annular bearing seals of complementary rectangular section to said spindle ends.

5. A duct valve assembly substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

6. An air-conditioning, heating, ventilation or refrigeration [air] duct valve seal comprising a flexible element with an opening to receive a valve spindle and a peripheral duct wall locating flange seal, and movable for sealing and supporting engagement with the duct walls andlor valve spindle.

7. A movable duct wall valve spindle seal for a valve drive spindle incorporating a locating surface for a valve operating member and comprising a seal member with an aperture of corresponding shape to said valve spindle surface profile and spaced peripheral locating and sealing flanges for movable sealing and bearing supporting engagement with the valve body or duct wall.