GB2297156A

GB2297156A - Controlling ventilation of premises

Info

Publication number: GB2297156A
Application number: GB9600941A
Authority: GB
Inventors: Pierre Charles Jardinier
Original assignee: Conseils Etudes et Recherches en Gestion de lAir CERGA
Current assignee: Conseils Etudes et Recherches en Gestion de lAir CERGA
Priority date: 1995-01-17
Filing date: 1996-01-17
Publication date: 1996-07-24
Anticipated expiration: 2016-01-17
Also published as: FR2729461B1; ES2130900B1; IT1281674B1; ITMI960063A1; FR2729461A1; GB2297156B; DE19601453B4; DE19601453A1; ES2130900A1; ITMI960063A0; GB9600941D0

Description

CONTROLLING VENTILATION OF PREMISES 2297156 The present invention relates

to controlling ventilation of premises, for example to a device for adjusting the passage cross-section of an air ventilation aperture.

The ventilation of premises may be controlled according to the conditions prevailing in those premises, in particular according to the humidity conditions. Such control can be provided by means of a ventilation flow rate regulator mechanism which acts on the flow rate by opening an extraction aperture to a greater or lesser extent, for example by acting on the angular position of a flap or of flaps located in a ventilation passageway. If it is desired to ensure a flow rate required by official regulations, such as a suction flow rate in a kitchen during the preparation of meals, termed forced flow rate, this must be provided irrespective of the possible opening of the regulated part. To this end this passageway may be provided with a substantial additional open area, capable on its own of providing the required forced flow rate even in the event of minimal opening of the regulated part. In some cases of substantial needs, the open section may then be very much greater than would be necessary, and this may result in a substantial energy cost in winter time, when hot air is extracted from the premises to be replaced by cold air. The excessive opening of the aperture could also result in transmission of noise between the premises in question and neighbouring premises.

According to the present invention, there is provided a ventilation control device comprising an aperture restriction member, movable to vary the effective cross-section of a ventilation passageway, first control means coupled to the aperture restriction member and operable to control the positioning of that member so as to impose a limit upon the said effective cross-section whilst permitting selectable movement of that member in a direction which does not cause the said limit to be breached, and second control means which can be operated selectively to vary the said effective cross-section by causing such movement of the said member.

One embodiment of the present invention comprises on the one hand a first mechanical actuator designed to cause the position of a flap to vary as a function of a parameter, such as humidity or C02 content, or serving to place the flap into a preset position corresponding for example to a statutory flow rate requirement, and on the other hand a second mechanical actuator designed to bring about at least the actuation of this flap in a direction of enlargement of the passage cross-section, a disengagement device being provided between the first actuator and the flap, so as to permit the further movement of the latter under the action of the second actuator.

The first actuator may be a proportional control device of the hygrometric type or of the type controlled according to the C02 content inside the premises, or may equally be a device serving to set the flap in a position determined by an installer in order to meet the statutory flow rate need of a dwelling. So long as the second actuator is not used, the flap functions in conventional manner with respect to the first actuator.

The second actuator may also, for its part, be controlled according to the relative humidity or to the C02 content, with a different range from the first actuator or a threshold. This second actuator may more usually be constituted by a manual or automatic control device which serves to ensure an additional flow rate in the event of more substantial specific pollution (kitchen, shower, toilet etc.). The additional flow rate obtained by further opening of the flap between the position resulting from the first actuator, and the position resulting from the action of the second actuator makes it possible to obtain-in precise manner the passage cross-section for the desired flow rate of air. The time during which the second actuator acts may be, for example, fixed by a timer which serves to limit the duration of the accelerated flow rate and therefore the heat losses.

Advantageously, the disengagement device comprises a mechanism for resilient return of the flap into its position deEmed by the first actuator, when the action exerted by the second actuator ceases.

The second actuator therefore acts on the flap only in the opening direction of the latter, the flap being brought back into its position provided by the first actuator as soon as the action exerted by the second actuator ceases.

Moreover, the force exerted indirectly by the resilient return mechanism on the first actuator, during the action of the second actuator on the flap, is relatively weak in comparison with the force brought into play for the functioning of the first actuator, the ratio of the respective forces being of the order of 1 to 3, in order not to disturb or to damage the mechanism of the first actuator. This resilient return permits a functioning of the aperture in a position other than the vertical, and prevents the occurrence of "beating".

In one embodiment of the present invention linking means between the first actuator and the flap on which it acts comprise a first movable piece, guided in movement, on which the actuator acts and a second piece which is coupled to the flap, the second piece being movable relatively to the first piece so that when the actuator acts on the first piece in a flap opening direction, it drives the second piece which ensures the movement of the flap in the opening direction and whereas during the additional pivoting of the flap by the second actuator the second piece moves relatively to the first piece, in opposition to the action of a return spring disposed between the first and the second piece, tending to bring the second piece back into contact with the first piece in opposition to the movement resulting from the operation of the second actuator.

In practice, the first actuator acts mechanically on the first piece which, in its movement, drives the second piece, the latter imposing on the flap its degree of opening because of coupling between this second piece and the flap. When the second actuator acts on the flap in a direction for opening the flap, a phenomenon of disengagement of the flap from the first actuator is brought about by movement of the second piece in relation to the first. When the second actuator ceases to act on the flap, the return spring brings the second piece back into contact with the first, in the course of which movement the flap moves in a closing direction so as to resume the position which results from the information supplied by the first actuator.

In one such embodiment of the present invention, the first and second pieces are constituted by two pieces guided longitudinally on a single support, the first of which is movable in both directions under the control of the first actuator, and comprises a heel or the like bearing against a part face to face with the second piece so as to drive the latter in translation in the direction for opening the flap.

In another such embodiment of the present invention, the first and second pieces are constituted by two pieces mounted to pivot about a single axis, the first of which is driven in both directions under the control of the first actuator and comprises a heel or the like bearing against a part face to face with the second piece so as to drive the latter in rotation in the direction for opening the flap.

Advantageously, the coupling between the second piece and the flap is obtained through the intermediary of a crank-shaped lever, bent twice, one end of which is keyed onto one end of a flap spindle, when the latter is pivoting, and the other end of which is fitted into a hole in the second piece, and the second actuator acts directly or indirectly on a crank keyed onto the other end of the flap spindle.

A crank-type system may be used when the piece for driving the flap moves linearly or when this piece is driven in rotation.

The ventilation aperture equipped with a device embodying the present invention may comprise a single flap, or two flaps one of which is operated primarily by the first actuator and secondarily by the second actuator beyond the position provided by the first actuator and independently of the latter, and the other of which is operated solely by the second actuator and directly under the control of the latter.

Advantageously, the flap or flaps are mounted on a detachable box fitted in the aperture, the ends of the bent levers being fitted into holes, by way of wedge- shaped entries, made in the driving pieces associated with the actuators. It is therefore very easy to remove, by simple extraction, the box equipped with its flaps, in order to carry out cleaning, for example.

Lastly, in order to prevent noise from shocks or vibrations during the movement of the flaps, in particular when slightly open, one of the flaps is arranged so as to pass in front of the other, without collision in a travel beyond the position defined by end-of-travel stops.

Reference will now be made, by way of example 5 only, to the accompanying drawings, in which:

Figure 1 is a front view partially in perspective and partially in crosssection, of a first device fitted to a ventilation aperture with two closing flaps which pivot in opposite directions to one another; Figure 2 is a perspective view, partially sectioned, and to an enlarged scale, of parts of the device of Figure 1; Figures 3 and 4 are two views similar to Figure 1, showing the device in respective further functioning dispositions; Figures 5 and 6 are two front perspective views showing respective different operating dispositions of a second device, embodying the present invention and having two flaps pivoting in the same direction.

Figure 1 shows an air extraction aperture 2 in a technical room of premises, for example a bathroom, a kitchen or a toilet if the premises is a dwelling.

This air extraction aperture is fitted with a box 1 provided with an aperture 3, the effective cross-section of which can be adjusted through the intermediary of two flaps 4 and 5 pivoting in opposite directions to one another on two parallel spindles 6 and 7 respectively. The variation in the angular position of the two flaps 4 and 5 serves to cause the effective passage cross-section to vary so as to adapt the flow rate of air to provide the required ventilation.

The adjustment of the angular position of the two flaps 4 and 5 is brought about by two actuators, one of which is shown in the left part of the Figure and is an automatic hygrometric actuator comprising a braid 8 the length of which varies as a function of the humidity, and the other of which is an actuator 9 shown in the right part of the drawing and is for example a manual actuator serving to enlarge the passage cross-section to a maximum when the ventilation needs so require.

One end of the braid 8, the lower end, is fixed and securely attached to a framework of the apparatus, whereas its upper end is fixed onto a first part 10 slidably mounted on the framework of the apparatus.

This part 10 is subject to the action of a return spring 12 which acts upwardly on it, in a direction of longitudinal extension of the braid 8. When the air is dry, the length of the braid 8 is at a minimum, and the part 10 occupies a low position. on the other hand, when the degree of humidity increases the braid 8 lengthens, and the first part 10 moves upwards, under the action of the spring 12. A part 13 is mounted on the first part 10, so that the parts 10 and 13 slide in the same directions as one another. A transverse face of the part 13 abuts against a heel 14 of the part 10, this abutment being maintained under the action of a return spring 15, one end of which is fixed to the lower end of the part 10 and the other end of which is fixed to the part 13. It may be seen, in particular in Figure 1, that a clearance i exists between opposing faces of the parts 10 and 13 permitting an upward relative movement of the second part 13 with respect to the first part 10. The second part 13 has a gap (or hole) 16 having a conical (progressively narrowing) entry zone into which one end 17 of a crank-shaped bent lever 18 is fitted. The other end of the lever 18 is keyed onto the spindle 6. The orientation of the lever 18 is such that it drives the flap 4 in an opening direction when the part 13 is moved upwards.

The second actuator 9, shown on the right hand slide of Figure 1, has an output rod 20 acting on a link 22. This link 22 can be moved downwards by operation of the actuator 9. In the link 22 is provided a hole 23 with a conical entrance into which is fitted one end 24 of a crank lever 25 the other end 26 of which is keyed onto the spindle 7 of the second flap. The assembly of the crank lever 25 is such that the spindle 7 drives the flap 5 towards an open position when the link 22 is moved downwards. During its downward displacement movement, the lower end of the link 22 may bear against one end 27 of a crank lever 28, the other end 29 of which is keyed to the end of the spindle 6 of the flap 4 opposite to the end equipped with the crank lever 18. The crank levers 18 and 28 are mounted in opposition so that a downward movement of the link 22 can result in an action on the crank 28 bringing about the opening of the flap 4.

The spindles 6 and 7 of the flaps 4 and 5 respectively are fitted by snapping home inside snap fit bearings which permit rotation of the flaps in the box 1. The fact that the ends of the levers 18 and 25 are fitted into respective holes having conical entry zones enables the box 1 to be removed easily, for example to permit cleaning of the assembly.

Starting from the position shown in Figure 1, as the humidity level increases in the room equipped with the ventilation aperture, the braid 8 lengthens and the movable equipment constituted by the parts 10 and 13 moves upwards, bringing about, through the intermediary of the crank lever 18, the tilting of the flap 4 in an opening direction, for example to a position as shown in Figure 3. If a temporary further increase in the ventilation flow rate is required, beyond the minimum limit set by the automatic first actuator, this can be achieved by means of the second actuator 9. Operation of the actuator 9 results in a downward movement of the link 22 which brings about a tilting of the flap 5 in the opening direction and also a further tilting of the flap 4 in an opening direction. This further tilting is possible by virtue of movement of the second part 13 relative to the first part 10, in opposition to the action of the spring 15. When the actuator 9 is deactivated, the link 22 is brought back up towards its position shown in Figures 1 and 3, and this results in the tilting of the second flap 5 towards its closed position, and the freeing of the crank 28, permitting the second part 13 to be brought back into abutment with the first part 10 by the spring 15, and consequently causing the flap 4 to return to the angular position which is imposed upon it solely by the first actuator 8.

Figures 5 and 6 show a second device, in which like components are designated by the same references as previously.

In this second device, the extraction aperture comprises two openings, associated respectively with the flaps 4 and 5. The two flaps 4 and 5 pivot in the same direction in this second device. The two crank levers 18 and 28 are orientated in the same direction, the movable assembly constituted by the parts 10 and 13 no longer moving upwards in order to bring about the opening of the flap 4, but downwards, like the link 22 driven by the second actuator 9. Other differences in principle and/or construction, between the device of Figs. 5 and 6 and that of Figs. 1 to 4, will be evident from the drawings.

As is self-evident, embodiments of the invention are not limited to those devices described above. For example the parts 10 and 13 of the movable equipment associated with the first actuator are not necessarily sliding, but could be pivoting; rotational driving of the flaps could be brought about not through the intermediary of a crank, but directly from the second movable part if this is pivoting; or the flaps could slide instead of pivot. A device could comprise only a single flap. The second actuator could act directly on the part for disengagement of the first actuator, 5 rather than through the intermediary of a flap.

Claims

CLAIMS:

1. A ventilation control device comprising an aperture restriction member, movable to vary the effective cross-section of a ventilation passageway, first control means coupled to the aperture restriction member and operable to control the positioning of that member so as to impose a limit upon the said effective cross-section whilst permitting selectable movement of that member in a direction which does not cause the said limit to be breached, and second control means which can be operated selectively to vary the said effective cross-section by causing such movement of the said member.

2. A device as claim in claim 1, wherein the said limit is a minimum value, the said second control means being operable selectively to move the said member so as to enlarge the effective cross-section.

3. A device as claimed in claim 1 or 2, wherein the said first control means comprise an automatic actuator operable to control the positioning of the said member in dependence upon a predetermined parameter.

4. A device as claimed in claim 3, wherein the said predetermined parameter is a humidity level.

5. A device as claimed in claim 3, wherein the said predetermined parameter is a C02 level.

6. A device as claimed in claim 1 or 2, wherein the said first control means comprise a manual mechanical actuator, selectively operable to preset the said limit.

7. A device as claimed in any preceding claim, wherein a linkage mechanism between the first control means and the said member includes resilient means for permitting such movement and for returning the said member to the limiting position determined by the first control means, when action of the said second control means on the said member is discontinued.

8. A device as claimed in claim 7, wherein the force transmitted to the first control means from the said resilient means, during action of the second control means on the said member, is relatively weak in comparison with the force brought into play by normal operation of the first control means, the ratio of the respective forces being of the order of 1 to 3.

9. A device as claimed in claim 7 or 8, wherein the said linkage mechanism comprises a first guided movable part, on which the first control means act, and a second part which is coupled to the said member, the said second part being movable relative to the said guided movable first part so that when the said first IS control means act on that first part, in a direction for enlarging the effective cross-section, that first part drives the said second part to move the said member so as to enlarge the effective cross-section, whereas during the said selectable movement of the said member by the second control means the said second part moves relatively to the first part, against the action of the said resilient means constituted by a return spring connected between the said first and second parts, which spring tends to bring the said second piece back into abutment with the said first part.

10. A device as claimed in claim 9, wherein the said first and second parts are guided longitudinally on a single support, the first part being movable in both directions along the support, under the control of the first control means, and having a heel portion for abutting against a face of the said second part so as to drive the second part in translation in the direction which causes enlargement of the effective cross-section.

11. A device as claimed in claim 9, wherein the first and second parts are pivotally mounted about a single axis, the first part being movable in both directions about the axis, under the control of the first control means, and having a heel portion for abutting against a face of the said second part so as to drive the second part in rotation in the direction which causes enlargement of the effective crosssection.

12. A device as claimed in claim 9, 10, or 11, wherein coupling between the said second part and the said member is provided by a crank-shaped lever bent twice, one end of the lever being connected to one end of a spindle on which the said member pivots, and the other end of the lever being fitted into a gap in the said second part, the second control means acting directly or indirectly on a crank-shaped lever keyed onto the other end of the said spindle.

13. A device as claimed in claim 12, wherein the said first member comprises a flap movable in a box adapted to be detachably located at one end of the ventilation passageway, one end of the at least on of the crank-shaped levers being fitted, by the way of a progressively narrowing insertion passageway, into a gap in the driving portion associated with the corresponding control means.

14. A device as claimed in any preceding claim, including a further aperture restriction member the positioning of which is controlled by the second control means.

15. A device as claimed in claim 14, wherein, in order to prevent noise from shocks or vibrations during movement of the said aperture restriction members, constituted respectively by first and second flaps, one of those flaps is arranged so as to pass in front of the other, without colliding with the other, when travelling beyond a position defined by end-of-travel stops.

16. A ventilation control device substantially as hereinbefore described with reference to Figs. 1 to 4, or to Figs. 5 and 6 of the accompanying drawings.