Ventilation system with axial fan and integrated accelerator/deflector

Abstract

A ventilation system for an air or gaseous fluid has a housing having an inlet (50) and an outlet (52), an axial fan (16) and an accelerating/deflecting structure (18). The axial fan has a casing (36) attached to the housing. Moreover, the axial fan (16) has a motor mounted within the casing and blades (32) also mounted within the casing to generate a flow of said fluid in an axial direction. The accelerating/deflecting structure (18) is devised and positioned to orient the flow generated by the axial fan (16) in a direction transverse to said axial direction. The accelerating/deflecting structure (18) can either be mounted upstream or downstream of the axial fan (16). Furthermore, the accelerating/deflecting structure (18) can either be mounted within or outside the housing.

Description

RELATED APPLICATION(S)

This application is a continuation of International Patent Application No. PCT/CA2004/000179 filed on Feb. 10, 2004, which claims benefit of Canadian Patent Application Nos. 2,418,636 and 2,447,334 filed on Feb. 10, 2003 and Oct. 31, 2003 respectively, which are herein incorporated by reference.

FIELD OF THE INVENTION

The present invention generally relates to fans used in a residential, commercial, industrial and institutional context. More precisely, the invention relates to a new ventilation system with an axial fan and, preferably, an integrated accelerator/deflector.

BACKGROUND OF THE INVENTION

In standard ventilation systems, in particular those used in bathrooms, the fan motor is always fixed to a support, either on an inner ventilator wall opposite the air inlet or on a wall adjacent to the inlet. Such a configuration causes turbulence problems in the fluid flow to be evacuated as well as creating phenomena of air backflow and noise. Another problem associated with standard ventilation systems arises from the transmission of vibrations from the motor to its support structure, with the noise generated by this transmission.

French patent FR 1255721 teaches a ventilator suspension system, particularly for kitchen ventilators, for which reductions in noise during its operation is a very important feature. This invention describes a suspension system that allows significant tangential motion of the axial fan motor which is suspended in a surrounding structure, while reducing axial motion of the fan motor, thus significantly reducing the noise being output from the ventilator.

German patent DE 91 08 745 U1 discloses a motor support system comprising a holding body made of rubber-elastic material with a surrounding ring part which spans around an intermediate bush surrounding a stator of an electric motor and holds in on a motor holder. In this construction, three arm parts are additionally provided which are uniformly distributed along the circumference, are molded onto the ring part and cause an additional support between the motor housing and the intermediate bush.

Most ventilators used in washrooms rely on propeller or centrifugal fans to create the required airflow through the ventilator.

Unfortunately, prior art devices in this field frequently are prone to premature clogging and corrosion, while having disappointing performances in terms of ventilating capacity.

In spite of the teachings of prior art, the above-described problems and issues with standard ventilation systems remain. Thus there still exists a need for a ventilation system which can better avoid the existing problems of turbulence, backflow, noise and vibration as well as the problems of premature clogging and corrosion.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a new ventilation system with an axial fan and, preferably, an integrated accelerator/deflector.

Even though the system described hereinafter and shown in the following drawings is essentially an air ventilation system designed for washrooms, it can also be used in other fields including audio-video systems, home appliances, ventilation systems, heating/refrigeration, kitchens, air conditioning, as well as ventilation systems made to forcibly evacuate smoke, heat or different gases or residues.

A first original feature of the present invention resides principally in the positioning and use of an axial fan which is fixed to the housing of the ventilator being used to evacuate the air (or other gaseous fluid). Another original feature of this invention resides in that the air or gaseous fluid must flow through an accelerator/deflector integrated to the ventilator housing and either mounted within or outside the housing, in order to improve the flow towards the ventilator outlet.

More specifically, the invention provides a ventilation system for an air or gaseous fluid comprising a housing having an inlet and an outlet, an axial fan and an accelerating/deflecting structure. The axial fan comprises a casing attached to the housing. The axial fan further comprises a motor mounted within the casing and blades also mounted within the casing to generate a flow of said fluid in an axial direction. The accelerating/deflecting structure is devised and positioned to reorient the flow generated by the axial fan in a direction transverse to said axial direction. The accelerating/deflecting structure can either be mounted upstream or downstream of the axial fan. Furthermore, the accelerating/deflecting structure can either be mounted within or outside the housing.

The present invention eliminates the backflow and air leak problems through a positioning of the axial fan which is assembled between two walls of the ventilator housing and using a sealing element between the fan and the housing. This type of assembly, when used in combination with an accelerator/deflector integrated to the housing, improves the fluid flow through the ventilator and therefore results in improved performance with respect to the ventilating capacity of the system. The accelerator/deflector improves the efficiency in terms of flow (inft³/min) at the outlet of the ventilator, as it decreases turbulence in the flow.

The ventilation system according to the present invention offers performances several times superior to those obtained with prior art systems used in the above-mentioned fields for the removal of air from enclosed spaces. Furthermore, this system facilitates removal of undesirable particulate matter including mould, bacteria, solvent vapours, toxic gases, pesticides, foul odours, carbon monoxide, cooking residues, and dust. Moreover, when used, for example, in combination with Ventiflex™-type ducting which is known as a flexible, lightweight, durable ducting specifically designed to optimise the conveying of large volumes of air, safely and cleanly, performance is exceptional. The system has been designed to operate in different environments of varying temperature and humidity.

The system according to the present invention not only results in improved performance with respect to overall air flow, but also results in remarkable acoustic qualities surpassing those of existing ventilation systems under similar conditions. In addition, as opposed to systems that currently exist in the market, the noise level of the ventilator of the present invention does not increase proportionally with an increase in the airflow going through it.

In addition to the above-mentioned advantages, the ventilation system according to the invention does not require any maintenance or cleaning during all of its useful life, while existing systems tend to get dirty with dust and residues floating in the air. Moreover, the system is not vulnerable to corrosion in normal operating conditions in the presence of humid air in a washroom or any chemical fume produced by an industrial process, contrary to existing ventilation systems.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention and its advantages will be more easily understood after reading the following non-restrictive description of preferred embodiments thereof, made with reference to the following drawings in which:

FIG. 1 is a perspective view of a ventilation system according to a first preferred embodiment of the invention wherein an accelerator/deflector is mounted outside the ventilator housing;

FIG. 2 shows a cut perspective view of a ventilation system according to a second preferred embodiment of the invention wherein an accelerator/deflector is mounted within the ventilation system housing;

FIG. 3 shows a cut perspective view of a ventilation system according to a third preferred embodiment of the invention wherein an accelerator/deflector similar to the one shown in FIG. 1 is mounted within the ventilation system housing;

FIG. 4 is an exploded view of the axial fan used in the ventilation system shown in the previous figures;

FIG. 5 is a cut side view of the ventilation system shown in FIG. 1; and

FIG. 6 is a cut side view of the ventilation system shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the first preferred embodiment of the invention shown in FIGS. 1 and 5, the ventilation system (10) for air or other gaseous fluids comprises a housing (12) through which the air or fluid flows. An axial fan (16) is fixed to the housing (12). The ventilation system (10) also comprises an accelerator/deflector (18) used to improve the air or fluid flow through the housing (12).

FIG. 2 shows another type of ventilation system (10) according to a second preferred embodiment of the invention, wherein the accelerator/deflector (18) is mounted within the ventilation system housing (12).

FIG. 3 shows a cut perspective view of a ventilation system (10) according to a third preferred embodiment of the invention, wherein an accelerator/deflector (18) similar to the one shown in FIG. 1 is mounted within the ventilation system housing (12).

As shown in FIG. 4, the axial fan (16) comprises a motor (20) in which two sets of ball bearings (24 and 26) are installed on either end of the drive shaft (22) which transmits the motor power. This type of motor assembly creates a better dynamic equilibrium when the motor is running. Moreover, this type of motor assembly decreases significantly problems related to bending moments in standard motor assemblies that have rotor blades placed at one of the extremities of the drive shaft. This accentuates problems due to the forces which sometime overcome the elastic limits of the materials used in such motor assemblies and thus lead to irreparable plastic deformations which are responsible for the premature wear of different components, including the ball bearings, the rotor blades and even the drive shaft.

Also as shown in FIG. 4, the motor (20) comprises a stator (28) and a rotor (30). Blades (32) for the fan are attached directly to the rotor (30) and are built as a single unit. When assembled with the stator (28), this type of assembly results in improved dynamic stability as radial and axial forces are reduced and the useful lifetime of components is increased compared to existing products. In addition, a spring element (34) is placed between the two sets of ball bearings (24 and 26) which creates a constant tensile axial force and results in improved stability. The ball bearings (24 and 26) are tightly installed to create a proper radial balancing effect and therefore a better dynamic equilibrium effect for rotational speeds varying between 400 and 10 000 rpm.

A motor casing (36) covers all the motor (16) components. The motor casing (36) comprises support arms (38) which link the center of the casing (35) holding the motor (16) assembly to the external part (40) of the casing (36). A sealing element (42) is installed around the periphery (44) of the casing (36). With the motor casing (36) installed in the ventilator housing (12), the sealing element (42) is the principal contact element between the fan (16) and the external wall (14) of the housing (12). This type of assembly eliminates air leaks from the housing (12) as well as decreases the transmission of vibrations from the moving parts of the motor (16) to the housing (12).

FIGS. 5 and 6 are cut side views of the ventilation systems shown in FIGS. 1 and 2 respectively. These figures illustrate the common aspects between the two systems according to preferred embodiments of the present invention. In both cases, the ventilation system (10) comprises a housing (12) having an inlet (50) and an outlet (52), an axial fan (16) and an accelerating/deflecting structure (18). The axial fan (16) comprises a casing (36) attached to the housing (12). The axial fan (16) further comprises a motor (20) mounted within the casing (36) and blades (32) also mounted within the casing (36) to generate a flow of said fluid in an axial direction. The accelerating/deflecting structure (18) in both cases is devised and positioned to orient the flow generated by the axial fan (16) in a direction transverse to said axial direction.

In an alternate preferred embodiment, the locations of the axial fan and the accelerator/deflector are reversed with respect to each other. In this configuration, the accelerating/deflecting structure is mounted upstream of the axial fan, instead of downstream as described in the previous embodiments.

The system in accordance with a preferred embodiment of this invention shown in the drawings is generally made of metallic materials. However, the invention is not limited to that type of material. The system can thus be manufactured from different plastics, composite materials or various alloys. Furthermore, the shape of the axial fan motor, the motor casing, the shape of the accelerator/deflector, the shape of the housing and the rotor blade shapes are elements among others that could be modified without departing from the scope of the present invention.

A system as shown has been manufactured from the following materials and has proved to offer the following performance characteristics:

Elements                Characteristics
Outer housing           Aluminum
Blade material          Plastic reinforced with thermoplastic glass
                        PBT.UL94V-0
Operating temperature   −20° C. to 80° C.
Power requirements      1 min to 1500 VAC 50/60 Hz 110 V/60 Hz and
                        220 V/50 Hz
Standards               E176286, CSA: LR109863-1, P/N 1123HBT
Air flow                Varying between 10 and 15 000 ft3/min
Rotational speed of fan Varying between 400 and 10 000 rpm
Electrical Current      Varying between 0.10 and 20 A
Static pressure         5.8 to 7 mm of water

Although the present invention has been explained hereinabove by way of a preferred embodiment thereof, it should be pointed out that any modifications to this preferred embodiment within the scope of the appended claims s not deemed to alter or change the nature and scope of the present invention. The great rigidity, stability, durability, high capacity and low noise output qualities of this new system makes it an interesting product for use in several fields as described above.

Claims

1. A ventilation system for an air or gaseous fluid comprising:

a housing having an inlet and an outlet;

an axial fan;

and an accelerating/deflecting structure,

wherein the axial fan comprises a casing attached to the housing, a motor mounted within the casing and blades also mounted within the casing to generate a flow of said fluid in an axial direction, and

wherein the accelerating/deflecting structure is devised and positioned to orient the flow generated by the axial fan in a direction transverse to said axial direction.

2. A ventilation system according to claim 1 wherein the accelerating/deflecting structure is mounted downstream of the axial fan.

3. A ventilation system according to claim 1 wherein the accelerating/deflecting structure is mounted upstream of the axial fan.

4. A ventilation system according to any one of claims 1 to 3 wherein the accelerating/deflecting structure is mounted within the housing.

5. A ventilation system according to any one of claims 1 to 3 wherein the accelerating/deflecting structure is mounted outside the housing.

6. The ventilation system according to any one of claims 1 to 5 wherein the axial fan motor further comprises a stator and a rotor and wherein the blades are integrated to the rotor to form a single component.

7. The ventilation system according to any one of claims 1 to 6 wherein the axial fan motor comprises a drive shaft surrounded by a spring element and a set of ball bearings located at both ends of the spring element.

8. The ventilation system according to any one of claims 1 to 7 wherein a sealing medium is located at the interface where the housing and the axial fan casing are attached to each other.

9. Use of the ventilation system according to any one of claims 1 to 8 for ventilation of a washroom.

10. Use of the ventilation system according to any one of claims 1 to 8 for ventilation of audio-video systems and home appliances.

11. Use of the ventilation system according to any one of claims 1 to 8 for ventilation in air conditioning systems.

12. Use of the ventilation system according to any one of claims 1 to 8 for evacuation of smoke, heat, gases and residues from rooms.