WO1993002325A1

WO1993002325A1 - Air-flow control member with a removable valve disc

Info

Publication number: WO1993002325A1
Application number: PCT/SE1991/000504
Authority: WO
Inventors: Curt DÄVERMO
Original assignee: PRIMAL AB
Current assignee: PRIMAL AB
Priority date: 1990-01-26
Filing date: 1991-07-22
Publication date: 1993-02-04
Anticipated expiration: 1994-01-22
Also published as: SE9000276L; SE467676B; SE9000276D0

Abstract

Air terminal device comprising a tube formed housing (2) with a circular internal cross section, which is provided with a coaxial, detachable hub (8) which carries a settable movable covering means (15) which is settable versus the outside of the housing, whereby the hub (8) has at least three radially arranged arms (9, 10, 11), which protrude at equal distances from the hub and with essentially equal mutual angular distances and which arms can be attached to the housing, whereby the arms (9, 10, 11) of the hub (8) with its outer ends engage into corresponding openings (12) provided in the housing wall (2), and that one of the arms (11) is provided with means (20) arranged to temporarily reduce its length, in order to allow the hub (8) to be moved in the direction of this arm and thereby pull the rest of its arms out of engagement with their openings in the retainer wall.

Description

Air-flow control member with a removable valve disc.

The present invention refers to an air terminal device between a channel system and a room and refers to a device at such an air terminal, which makes possible a rapid and simple assembly and disassembly of the separate parts of the air terminal device.

In office premises, classrooms and other private or public rooms, air terminal devices are provided between the present room and behind a wall discharging ventilation duct through which is transported varying air quantities. By the time such ducts and air terminal devices will receive depositions of dust and other contaminations in the channel system and on the surfaces of the air terminal device. For the sake of health for those staying in the room concerned, and in order to obtain a correctly calculated amount of air in advance, these ducts and air terminal device surfaces have to be cleaned, which is very difficult at present common designs of air terminal devices, and in certain cases even impos¬ sible to carry out without extensive operations in the building in question.

The air terminal device on the side facing the room is provided with a valve disc which is to its position axially settable, and by means of which the opening of the air terminal device can be controlled by its size, and which valve disc also works as a covering lid, which conceals the air terminal device and the duct behind the same for those present in the room. This valve disc is commonly provided with a spindle, which can be screwed inwards to a desired degree in a hub provided coaxially in the air terminal device with a threaded bottom hole. The hub is usually integrally formed with the air terminal device, and this means that the duct lying behind hardly can be cleaned without whole air terminal device and its retainer being disassembled, which is so complicated, that it is most frequently omitted, whereby neither the separate parts nor the duct will be cleaned.

DE-A-2018439 describes an airing valve with a coaxial hub, which in this carries an axially screwable valve cone and has three radial arms, which may be clamped against ramp formed resilient tongues which are inwards bent out from the inner wall of the valve housing. This hub can be disassem¬ bled by being turned such that the arms thereof are free from the tongues, but such a rotation may demand not unes¬ sential force if the arms have been wedged against the tongues. At a wrench in order to loosen the hub, the tongues thereby might be damaged, which may imply that the whole valve housing has to be exchanged. Moreover there is a risk that the tongues after some removals have lost their resili¬ ency, so that they do not give satisfactory locking func¬ tion, which again demands exchange of the whole valve hou¬ sing.

US-A- 3 155 027 describes a controllable air diffuser with a hub provided in a housing, which hub carries an axially settable valve disc, and the hub is fixed to the housing by means of three radial arms, which are secured by screws to axially inwards directed housing flanges positioned inside the housing behind the hub. Its true that this hub theoreti¬ cally by its screw and nut fastening gives a possibility of removal from the housing, whereby a duct situated behind could be reached, but since the fastenings are situated behind the hub inside the housing yet it should be necessary to remove the whole housing to reach the screws.

The object of the invention and most essential features

The object of the invention is to provide an air terminal device of the type stated in the preamble of the patent claim 1, which gives a possibility of a simple and rapid assembly and disassembly of the separate parts of the air terminal device and thereby also good possibilities of cleaning the surfaces of the air terminal device, and there¬ by also the surfaces which are facing the duct in operation position, as well as the duct itself without any change of the air flow previously set, and this has been accomplished by the air terminal device being provided with the features stated in the characterizing part of claim 1.

Description of the drawings In the following the invention will be described in greater detail with reference to the accompanying drawings, showing non limiting embodiments of the air terminal device accor¬ ding to the invention.

Fig. 1 shows an air terminal device provided with an arrang¬ ement according to the invention seen in a sectional view along the line I - I in Fig. 2.

Fig. 2 is a plan view of the air terminal device according to Fig. 1 seen from outside but with the valve disc removed. Fig. 3 shows a section through a hub along the line III -III i Fig. 2.

Fig. 4 shows in a view from the above an alternative em¬ bodiment of the hub in an air terminal device according to the invention, and Fig. 5 is a side view of the hub according to Fig. 4.

Fig. 6 in closer detail shows an opening in the valve hou¬ sing wall intended to receive and fix one of the retainer arms of the hub.

Description of preferred embodiments

Fig. 1 shows a section along the line I - I in Fig. 2 throu¬ gh an air terminal device comprising a valve housing 1 formed as an essentiallly cylindrical pipe spigot 2 with a radially outwards facing flange 3 provided at one end of the spigot and intended to be mounted against a wall about an air duct so that the other end of the spigot enters into the duct. The flange 3 is provided with screw holes 4, through which screws are to be screwed into a wall behind for fixing of the valve housing into position in the duct. The side of the valve housing opposite to the flange 3 has somewhat smaller diameter than the rest of the housing and the tran- sition between the two housing portions is provided with a shoulder running about the inner circumference of the hou¬ sing, forming a conical seat 5, with the major side facing the flange side. This shoulder serves as a seat for a sepa¬ rate, mainly conical pressure reducing device 6, which in Fig. 1 is shown with slightly cut off portions and designed as a funnel with a conical stepped wall, which serves to reduce the pressure in the duct and also contributes to reduction of sound. The pressure reducing device is held in its position by its seat 5, so that it cannot fall out, by m eans of a retainer device 7 comprising a central hub 8 and a number, in the example shown three spoke formed, radially outwards from the hub directed arms 9, 10, 11 (see Fig. 2), with the same length and the ends of which fit into openings 12 (Fig. 6) in the wall of the valve housing, situated just outside the conical seat 5. The hub 8 of the retainer device is formed as a bottom sleeve, the part of which is directed outwards is provided with an external thread 13 onto which can be screwed a corresponding internal thread on a sleeve 14 on a valve disc 15, which thereby can be secured by thre- ads to the bottom sleeve betweeen an inner position and an outer position where the inside of the valve disc is situa¬ ted at a distance from the valve housing flange and thereby forms a slot versus this of not unessential size. The valve disc 15 on its inside is provided with an insulating layer 16, which partly prevents precipitation of condensation water and partly also as sound absorption.

The hub 8, which thus partly carries the valve disc 15 and partly by the ends on its arms 9, 10 and 11 being engaged with the openings 12, or other suitable attachment devices, in the valve housing wall will be fixed into the valve housing, keeps the pressure reducing device in position in its seat 5. In order for the hub to be assembled and removed in a simple way, among others to a high degree faciliate cleaning of the duct behind, one of its arms, the arm 11 is designed to temporarily be shorted, so that the whole hub can be displaced in a direction towards the opening 12 former cooperating with this arm 11. In this way the fixed arms 9 and 10 may be pulled out of engagement with their cooperating openings 12 in the housing wall, and thereby the whole hub simply can be removed. For the hub to be assembled it is however required that the pressure reducing device is mounted in the correct position in the seat 5 in the valve housing wall. For this purpose the conical pressure reducing device 6 at its major end is provided with an axially out¬ wards running flange, while the openings 12 for the hub arms 9, 10, 11 are constituted by elongated slots provided in the valve housing, which slots such as is shown in Fig. 6, extend from the conical seat 5 and axially past the end of the pressure reducing device mounted in the seat, and these slots in their portion between the seat 5 and the level for the end plane for the pressure reducing device flange larger width than in th following portion, the width of which corresponds to the width of the ends of the hub arms 9, 10, 11, whereby the hub 8 only can be mounted in the valve housing when the pressure reducing device is mounted in th correct position in its seat. When the pressure reducing device 6 is not present in correct position, the ends of the hub arms will slide down into the broader portions of the openings 12, where they will not obtain any clamping or guiding, and the hub will lie loose in the valve housing.

In the embodiment shown in Fig. 1 to 3 the arm 11 is pro¬ vided with a guide, which is constituted by diametrically opposed recesses 17, 18 in the wall of the hub sleeve 8 placed slightly above the bottom of the sleeve, and which by means of upwards directed flanges 19 forms a slot in which is positioned a spring 20, which with one of its ends acts against the wall of the sleeve, and with its other presses against a shoulder 21 provided on the arm 11, so that the arm is prestressed to the position shown in Fig. 2. When the valve disc 15 shown in Fig. 1 has been screwed off from th hub sleeve 8 one may easily reach a grip 22 provided on the movable arm 11 and press this on to the hub 8, whereby the arm 11 comes out of engagement with its opening 12 in the housing wall. Thereafter the whole hub with arms can be brought in the opposite direction whereby the arms 9 and 10 as well come out of engagement with their openings 12 and the whole hub can be lifted out of the housing. Thereafter the pressure reducing device 6 can be lifted out for clea¬ ning of the same and of the duct lying behind and for pos¬ sibly an exchange of the pressure reducing cone and possibly damaged parts of the hub. Since the arm 11 on the side facing inwards is provided with a slot 23 with outwards directed hooks 24, the whole arm 11 may easily be removed from the hub sleeve, whereupon the spring 20 also is exposed to a possible exchange. Assembly of the hub and the whole air terminal device is then carried out in the reverse order in the same simple way. All parts of the hub with exception for the spring can be manufactured in a simple way in plas¬ tic without need for complicated tools or forming devices.

Fig. 4 in a view from the above and Fig. 5 in a lateral view show an alternative embodiment of the hub of the air termi¬ nal device, which as well as in the embodiment according to Fig. 1 to 3 comprises a bottom sleeve 8 with an external thread 13 and with three radial arms 9, 10 and 11a arranged with 120° mutual angular distance, which in the same way as in the previous illustrated example are going to be inserted in attachments in the housing of the air terminal device. The hub differs from the earlier shown embodiment by the arm 11a, the length of which temporarily can be reduced is provided with a hinge 25 between its ends, which makes it possible to fold the arm 11a, so that its end comes out of engagement with its attachment in the housing of the air terminal device. On the opposite side of the arm 11a cal- culated from the hinge a latch 26 is provided, which counte¬ racts that the arm 11a is folded about its hinge inadver¬ tantly. When one whishes to loosen the hub from the air terminal housing it is simple to loosen the latch 26 whereu- pon the arm 11a can be folded about the hinge. For the rest the function is the same as in the embodiment according to Fig. 1 to 3. Also in this case the hub can be manufactured in plastic, whereby the hinge 25 as well as the latch 26 in a simple known way may be formed directly in the plastic material.

The invention is not limited to the embodiments shown and thereby described, but modifications and variants are pos¬ sible within the scope of the following patent claims. In the examples shown the design has comprised three radial arms of which one has been possible to shorten temporarily, but it is understood that the hub can have several arms and thereby also several temporarily shortable arms.

The invention has been described in connection with an air terminal device, but it is understood that the same solution might find use in other applications where in a round drum there is a need to hold a coaxially placed hub by means of arms, which not to a greater extent reduces the flow area through the drum.

Claims

CLAIMS 1. Air terminal device of the type comprising an essentially tube ormed housing (2) with a circular internal cross section, which is provided with central in the housing coaxially located detachable hub (8) intended to carry a axially movable covering means (15), which is located again¬ st the outside of one end of the housing, for setting of a slot at the edge of said end of the housing, whereby the hub (8) shows at least three radially arranged arms (9, 10, 11;11a), which protrude at equal distances from the hub and with essentially equal mutual angular distances and which arms are attached to the inside of the housing wall, c h a r a c t e r i z e d t h e r e i n, that the arms (9,10, 11;11a) of the hub (8) with its outer ends engage into corresponding openings (12) provided in the housing wall (2), and that at least one of the arms (11;11a) is provided with means (17,18,20,21;25) arranged to tempora¬ rily reduce their length, in order to allow the hub (8) to be moved in the extension direction for this arm and thereby can pull the rest of its arms (9,10) out of engagement with their attachments (12) in the retainer wall.

2. Device according to patent claim 1, c h a r a c t e r i z e d t h e r e i n, that one of the arms (11) is movably arranged in its longi¬ tudinal direction in a guide (17,18) provided in the hub (8), and is prestressed in a direction against its fully extended position.

3. Device according to patent claim 2, c h a r a c t e r i z e d t h e r e i n, that the hub (8) is formed as an upwards open bottom sleeve, and that the guiding is constituted by recesses (17,18) arranged diametrically opposed to each other at a distance above the lower part of the bottom sleeve, whereby the rear part of the movable arm (11) extends through recesses, and between the bottom of the sleeve and the arm is provided a spring (20) arranged under action between the inner wall of the sleeve and a shoulder (21) on the arm (11) to prestress the same against its fully extended position.

4. Device according to patent claim 1, c h a r a c t e r i z e d t h e r e i n, that at least one of the arms (11a) is provided with a hinge (25) arranged between the ends of the arm, by means of which the length of the arm can be temporarily shorted.

5. Device according to patent claim 4, c h a r a c t e r i z e d t h e r e i n, that the arm (11a) provided with a hinge also is provided with an unlockable latch (26), which prevents unintentional bending of the arm about the hinge (25).

6. Device according to any of preceeding patent claims, whereby the housing (2) carries a internally provided pres¬ sure reducing device (6), c h a r a c t e r i z e d t h e r e i n, that the pressure reducing device is formed as a separate, essentially conical funnel, which is provided with a conical seat (5) in the housing and is held in the seat by the arms (9,10,11;11a) of the hub with their end portions contact the end rim of the pressure reducing device.

7. Device according to patent claim 6, c h a r a c t e r i z e d t h e r e i n, that the conical pressure reducing means (6) at its major end is provided with an axially outwards extending flange, the openings (12) for the hub arms (9, 10, 11) being consti¬ tuted by elongated slots provided in the valve housing wall, which slots extend from the conical seat (5) and axially past the end of the pressure reducing means mounted in the seat (5), and that these slots in its portion between the seat (5) and the level for the end plane of the flange of the pressure reducing means has greater width than in the subsequently following portion, which has a width correspon¬ ding to the ends of the hub arms (9, 10, 11), whereby the hub (8) only can be mounted in correct position in its seat (5).