GB1602998A - Ventilators - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO VENTILATORS (71) We, VENTEC (AGRICULTURAL) LIMI TED, a British Company, of 9 Trinity Street, Colchester, Essex, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a ventilator assembly, and in particular to a ventilator assembly intended for fitting to a wall or roof of a building. The ventilator assembly of this invention incorporates a motordriven fan to obtain the required ventilation.

It is important that buildings in which livestock are kept, such as poultry houses, are maintained at a sufficiently high temperature for the well-being of the animals, and yet a sufficient supply of fresh air must be provided. There have been various proposals for ventilator assemblies for such buildings, designed to allow the intro duction of fresh air at a rate which will not reduce the temperature within the building to an unacceptably-low level. Though some of these proposals have employed motordriven fans to obtain the required ventilation flow rates, these previous arrangements however have been either inefficient in operation or somewhat complex and thus costly to manufacture.

It is an aim of this invention to provide a ventilator assembly suitable for installation for instance in an agricultural building such as a poultry house, which ventilator allows adjustment of the ventilation.

According to this invention, there is provided a ventilator assembly for a building, comprising a duct adapted for mounting within a building on a wall or roof thereof so as to communicate with the exterior, a motor-driven fan mounted within the duct such that the fan may impell air inwardly through the duct, the duct having a circular cross-sectional upstream of the fan and there being a sleeve also of circular cross-section and which is mounted co-axially with the duct so that the circumferential surfaces of the sleeve and duct may co-operate, the duct and sleeve having a pair of apertures which may be brought into and out of registration on rotation of the sleeve about its axis and through which apertures when at least partially in registration air amy be drawn into the duct by the fan, the ventilator assembly further including valve means for controlling the communication of the duct to the exterior which valve means is located upstream of said apertures and which is operatively coupled to the sleeve such that when the apertures are fully in registration the valve means is closed and when the sleeve closes the aperture in the duct the valve means is fully open, whereby on installation of the ventilator assembly in a building, the air impelled by the fan may be selected to be solely fresh air, blends of fresh air and recirculated air, or solely recirculated air, by simultaneous adjustment of the rotatable sleeve and valve means.

It will be appreciated that with the ventilator assembly of this invention, the motor-driven fan may draw air either from within the building itself, or fresh air from the exterior of the building or blends of these airs. Thus, if the outside air temperature is too low, the combination of the sleeve and valve means can be adjusted to close the valve means, so that air is recirculated within the building, whereas if the air temperature is sufficiently high the combination of the sleeve and valve means can be adjusted so that no air is recirculated, and the fan only draws fresh air from outside the building.

It is preferred for the valve means to be mounted on the part of the duct also having the co-axial sleeve mounted thereon, and conveniently that part of the duct is provided with a pair of flanges one at each axial end thereof for mating with corresponding flanges on other parts of the duct.

In this way, the complete assembly of the valve means and the sleeve may be removed by unbolting the flanges.

Preferably, both the sleeve and the cylindrical wall of the duct are each provided with a plurality of apertures which may gradually be brought into or out of registration on rotation of the sleeve. Conveniently six such pairs of apertures are provided around the respective cylindrical walls of the duct and the sleeve, and each such closable aperture is preferably of the same angular extent and spaced equally from the adjacent apertures.

The valve means is coupled to the rotatably sleeve for simultaneous operation therewith, and a preferred arrangement comprises a plate mounted in the duct upstream of the or each closable aperture and having at least one slot therein, there being a co-operating valve element having a similar slot and which may be moved to open and close the slot in the plate. The plate and valve element may each have a similar array of sector-shaped slots, the angular spacing between the sectors being at least as great as the angular extent of each sector, and the valve element being rotatably mounted on the plate about the origin of the sectors, whereby the slots may be opened or closed fully on rotation of the valve element.

Preferably the angular extent and spacing of each slot and the number thereof corresponds directly to the closable apertures, whereby the valve element may directly be coupled to the rotatable sleeve, but in such a relative disposition that when the apertures are in complete registration with those in the sleeve, the slots are fully closed, and vice versa.

A manually-operable control may be provided for adjusting the sleeve and valve means, by rotating the rotatable sleeve and valve element in the case of the preferred form of valve means -- though power- operated means may instead be provided if required. For example, an electric motor may drivingly be coupled to the sleeve, so as to effect rotation thereof. A plurality of ventilator assemblies of this invention may be installed in a building, and in particular in a single room of the building such as in a poultry house, and in this case, the sleeves of each ventilator may be coupled together for simultaneous operation, for example by a single electric motor. By providing a temperature sensor in the room or building and an appropriate control arrangement, the operation of the motor may be fully automatic, to give the required degree of ventilation. The control arrangement may also serve to control the operation of the motor-driven fan.

The motor-driven fan conveniently employs an electric motor, and for such a fan, control means may be provided to sense if there is a power failure, and then to allow the damper unit to be adjusted fully to open the valve means, so that natural convection to the exterior may take place in the event of a power failure. This may be achieved for example by spring-loading the sleeve so as normally to return to an adjustment in which the valve means is fully open, and in the event of a power failure, the damper unit is released to moved under the spring-loading.

By way of example only, one specific embodiment of the invention will now be described, reference being made to the accompanying drawings, in which: Figure 1 is a cross-sectional view through a ventilator assembly constructed in accordance with this invention and fitted in the roof of a building; and Figure 2 is a sectional view taken on line A-A marked on Figure 1.

Referring to the drawings, there is shown a ventilator assembly of this invention intended for use in a poultry house. A plurality of such ventilators will normally be provided along the apex of the roof, for simultaneous operation to ventilate the poultry house.

The ventilator assembly comprises a cylindrical duct section 10 secured to an upper duct section 11, the section 11 having a flange 12 by means of which the ventilator is mounted in a roof. A circular hole is provided in the roof at the apex thereof, and the flange 12 is located on the outside of the roof, suitable bolts (not shown) being used to clamp the section 11 to the roof. A cowl 13 is fitted over the section 11.

The lower end of the duct section 10 is formed with a flange 14, to which is bolted a fan unit 15 having a corresponding flange 16. Below the fan unit 16 is bolted a distributing nozzle 17, by means of co-operating flanges 18. The flange 14 is fitted with stays 19, tying the fan unit to the roof.

The fan unit 15 has a circular impeller 20 fitting closely within the inner periphery of the wall of the fan unit 16, the impeller being driven by an electric motor 21 mounted above the impeller 20. The direction of rotation of the motor 21 is such that the impeller draws air downwardly past the impeller for discharge through the nozzle 17.

The duct section 10 is formed as a valve assembly, and includes a cylindrical sleeve 22 fitting closelya gainst the outer periphery of the duct section 10 but mounted for rotation therearound. The sleeve 22 is provided with six equi-spaced circular apertures 23, each of circular shape and each of which may come into registration with a corresponding series of six circular apertures formed in the duct 10, on rotation of the sleeve 22.

Within the duct section 10, above the closable apertures therein, there is pro vided a circular plate 24 affixed to the inside wall of the duct section 10, the plate having six slots 25 therein each in the form of a sector. Rotatably mounted on the plate 24, about the axis of the duct section 10, is a valve disc 26 also having six slots 27 formed therein, each slot 27 in the form of a sector of the same angular extent and spacing as those slots 25 in the plate. The valve disc 26 is directly connected to the sleeve 22 by means of a link 28 extending through a slot in the wall of the duct section 10. The valve disc 26 and the sleeve 22 are however relatively disposed so that when the apertures in the duct section 10 are wholly in registration with the apertures 23 in the sleeve 22, the valve disc wholly obstructs the slots 25 in the plate 24, whereas when the slots in the valve disc and the plate are in registration, the apertures in the duct section 10 wholly are closed by the sleeve 22. Thus, the angular extent of each aperture and the angular extent of each slot should be the same and moreover the angular spacing between each aperture and each slot should be the same.

The valve assembly described above should be provided with some means for rotating the sleeve 22, so as to effect adjustment of the amount of fresh air introduced by the ventilator unit. The means of operation will however depend upon the precise installation in which the ventilator assembly is incorporated. For example, for a relatively small building or room, it may be practical to employ a manually-adjusted damper unit, in which case an appropriate handle arrangement may be attached to the sleeve 22, to effect rotation thereof.

On the other hand, if a plurality of ventilator assemblies of this invention are incorporated along the apex of the roof of a building, all the rotatable sleeves may be coupled together for simultaneous rotation.

Such coupling of the sleeves may be effected for instance by means of Bowden cables appropriately attached to the sleeves, or by means of rigid links hinged to arms extending radially from the sleeves 22. For an arrangement in which all the sleeves of a series of ventilator assemblies are coupled together, a motor may be employed to effect rotation of the sleeves, the motor conveniently being arranged in a separate unit and drivingly connected to the means provided for effecting simultaneous rotation of all the sleeves. Such a separate unit may incorporate a temperature sensor, the operation of the motor being controlled in dependence upon the temperature sensed, to obtain automatic control of the opening of all the valve assemblies.

All the valve assemblies may be springloaded towards the position in which the slots in plate are fully open. If the control unit is modified to incorporate an arrangement to detect a power failure and on detecting a power failure, to disconnect the motor from the means for effecting rotation of the sleeves 22, all the sleeves may simultaneously rotate under their springloading to the position in which the slots in the plate 24 are fully opened. This allows natural convection to take place through the ventilator, even though the motor 21 is inoperational.

WHAT WE CLAIM IS: 1. A ventilator assembly comprising a duct adapted for mounting within a building on a wall or roof thereof so as to communicate with the exterior, a motor driven fan mounted within the duct such that the fan may impell air inwardly through the duct, the duct having a circular cross-section upstream of the fan and there being a sleeve also of circular cross-section and which is mounted co-axially with the duct so that the circumferential surfaces of the sleeve and duct may co-operate, the duct and sleeve having a pair of apertures which may be brought into and out of registration on rotation of the sleeve about its axis and through which apertures when at least partially in registration air may be drawn in to the duct by the fan, the ventilator assembly further including valve means for controlling the communication of the duct to the exterior which valve means is located upstream of said apertures and which is operatively coupled to the sleeve such that when the apertures are fully in registration the valve means is closed and when the sleeve fully closes the aperture in the duct the valve means is fully open, whereby on installation of the ventilator assembly in a building, the air impelled by the fan may be selected to be solely fresh air, blends of fresh air and recirculated air, or solely recirculated air, by simultaneous adjustment of the rotatable sleeve and valve means.

2. A ventilator assembly as claimed in claim 1, wherein the section of the duct which defines the aperture is provided with a pair of flanges one at each axial end thereof for mating with a corresponding flange on other parts of the duct.

3. A ventilator assembly as claimed in claim 1 or claim 2, wherein there is provided a plurality of closable apertures around the cylindrical wall of the duct and also a corresponding plurality of apertures around the circumferential wall of the sleeve, whereby all the apertures may gradually be opened or closed simultaneously on rotation of the sleeve.

4. A ventilator assembly as claimed in any of claims 1 to 3, wherein the valve means comprises a plate mounted in the duct upstream of the apertures in the duct

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. vided a circular plate 24 affixed to the inside wall of the duct section 10, the plate having six slots 25 therein each in the form of a sector. Rotatably mounted on the plate 24, about the axis of the duct section 10, is a valve disc 26 also having six slots 27 formed therein, each slot 27 in the form of a sector of the same angular extent and spacing as those slots 25 in the plate. The valve disc 26 is directly connected to the sleeve 22 by means of a link 28 extending through a slot in the wall of the duct section 10. The valve disc 26 and the sleeve 22 are however relatively disposed so that when the apertures in the duct section 10 are wholly in registration with the apertures 23 in the sleeve 22, the valve disc wholly obstructs the slots 25 in the plate 24, whereas when the slots in the valve disc and the plate are in registration, the apertures in the duct section 10 wholly are closed by the sleeve 22. Thus, the angular extent of each aperture and the angular extent of each slot should be the same and moreover the angular spacing between each aperture and each slot should be the same. The valve assembly described above should be provided with some means for rotating the sleeve 22, so as to effect adjustment of the amount of fresh air introduced by the ventilator unit. The means of operation will however depend upon the precise installation in which the ventilator assembly is incorporated. For example, for a relatively small building or room, it may be practical to employ a manually-adjusted damper unit, in which case an appropriate handle arrangement may be attached to the sleeve 22, to effect rotation thereof. On the other hand, if a plurality of ventilator assemblies of this invention are incorporated along the apex of the roof of a building, all the rotatable sleeves may be coupled together for simultaneous rotation. Such coupling of the sleeves may be effected for instance by means of Bowden cables appropriately attached to the sleeves, or by means of rigid links hinged to arms extending radially from the sleeves 22. For an arrangement in which all the sleeves of a series of ventilator assemblies are coupled together, a motor may be employed to effect rotation of the sleeves, the motor conveniently being arranged in a separate unit and drivingly connected to the means provided for effecting simultaneous rotation of all the sleeves. Such a separate unit may incorporate a temperature sensor, the operation of the motor being controlled in dependence upon the temperature sensed, to obtain automatic control of the opening of all the valve assemblies. All the valve assemblies may be springloaded towards the position in which the slots in plate are fully open. If the control unit is modified to incorporate an arrangement to detect a power failure and on detecting a power failure, to disconnect the motor from the means for effecting rotation of the sleeves 22, all the sleeves may simultaneously rotate under their springloading to the position in which the slots in the plate 24 are fully opened. This allows natural convection to take place through the ventilator, even though the motor 21 is inoperational. WHAT WE CLAIM IS:

1. A ventilator assembly comprising a duct adapted for mounting within a building on a wall or roof thereof so as to communicate with the exterior, a motor driven fan mounted within the duct such that the fan may impell air inwardly through the duct, the duct having a circular cross-section upstream of the fan and there being a sleeve also of circular cross-section and which is mounted co-axially with the duct so that the circumferential surfaces of the sleeve and duct may co-operate, the duct and sleeve having a pair of apertures which may be brought into and out of registration on rotation of the sleeve about its axis and through which apertures when at least partially in registration air may be drawn in to the duct by the fan, the ventilator assembly further including valve means for controlling the communication of the duct to the exterior which valve means is located upstream of said apertures and which is operatively coupled to the sleeve such that when the apertures are fully in registration the valve means is closed and when the sleeve fully closes the aperture in the duct the valve means is fully open, whereby on installation of the ventilator assembly in a building, the air impelled by the fan may be selected to be solely fresh air, blends of fresh air and recirculated air, or solely recirculated air, by simultaneous adjustment of the rotatable sleeve and valve means.

2. A ventilator assembly as claimed in claim 1, wherein the section of the duct which defines the aperture is provided with a pair of flanges one at each axial end thereof for mating with a corresponding flange on other parts of the duct.

3. A ventilator assembly as claimed in claim 1 or claim 2, wherein there is provided a plurality of closable apertures around the cylindrical wall of the duct and also a corresponding plurality of apertures around the circumferential wall of the sleeve, whereby all the apertures may gradually be opened or closed simultaneously on rotation of the sleeve.

4. A ventilator assembly as claimed in any of claims 1 to 3, wherein the valve means comprises a plate mounted in the duct upstream of the apertures in the duct

and sleeve and having at least one slot therein, there being a co-operating valve element having a similar slot and which may be moved to open and close the slot in the plate.

5. A ventilator assembly as claimed in claim 4, wherein the plate and valve element each have a similar array of sector-shaped slots, the angular spacing between the sectors being at least as great as the angular extent of each sector, and the valve element being rotatably mounted on the plate about the origin of the sectors, whereby the slots may be opened or closed fully on rotation of the valve element.

6. A ventilator assembly as claimed in claim 4 or claim 5, wherein the valve element is directly coupled to the rotatable sleeve for simultaneous operation therewith.

7. A ventilator assembly as claimed in any of the preceding claims, wherein the rotatable sleeve and valve means are spring loaded so as normally to return to an adjustment in which the valve means is fully open.

8. A ventilator assembly substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.