The present invention relates to an extraction system for containing and removing vapours generated during application of films to a surface and, in particular, but not exclusively to the safe removal of spray mists, particulates and vapours generated during body repair and/or repainting of a vehicle.
A vehicle requiring body repair and/or repainting is subject to a number of different processes depending on the type of repair or repaint. For example the repainting process comprises a number of distinct stages including for example preparation for the paint, typically involving sanding the original surface to provide adhesion for the extra paint layers to be applied, or the removal of the paint film to provide adhesion for the layers of shaping filler that are to be applied to a dent and/or blemish in the surface. Polyester filler is normally used to reshape damaged areas to the pre-damaged state. After shaping, final surface preparation requires the application of a hi-build primer to enable final levelling and filling of very small imperfections. The hi-build primer or paint is usually applied using a spray gun or aerosol with a material transfer efficiency of between 50 to 80%. The spray gun or aerosol atomizes the paint or primer into a fine spray by using either compressed air or a propellant. The nature of this spray requires that undamaged surfaces adjacent the area to be repaired or repainted must be masked-off, that is covered, to prevent migration of the spray onto such.
The masked-off areas not only include adjacent surfaces of the vehicle, but often also adjacent vehicles and surfaces of the workshop, this is because if spray or overspray contacted clean or undamaged surfaces this would give rise to time consuming and costly removal thereof.
The paints, primers and materials used produce noxious vapours and environment and government regulations therefore require that these processes be carried out in a controlled environment such as a spray booth, preparation station or limited finish work station. Conventionally a dedicated spraybooth is provided within the workshop which provides an enclosed environment and all or part of the spraying process is carried out inside the controlled environment of the spraybooth. The spraybooth is usually equipped with an extraction system which draws the air containing the noxious vapours from the booth and then filters out hazardous chemicals therein before release of the cleaned extracted air into the atmosphere.
After the hi-build primer has been applied then it must be sanded to allow for any imperfections to be removed. Since the dedicated controlled environment is a critical resource within the workshop the vehicle or vehicle part is removed therefrom for this sanding operation. Once the sanding operations is complete the vehicle or part is re-masked and re-entered into the controlled environment for the further or final top coat of paint.
During re-assembly of painted parts of vehicles it is not uncommon to damage small areas of the newly painted surface. Typically this damaged area would have to be prepared and then repainted within the controlled environment, such as a spraybooth or limited finish workstation.
The dedicated controlled environment such as a spraybooth as mentioned above is a critical resource and the efficient and cost effective use thereof is essential to ensure profitability of the workshop. The continuous removal and re-entry of the vehicle or part thereof, whilst done to free the spraybooth for spraying and/or curing operations nevertheless leads to downtime reducing effective use of this facility. Furthermore, such a controlled environment requires a large building to house it and it is an expensive item to purchase, meaning that it is often not possible for local small workshops and garages to offer a paint and repair service. This is not only an inconvenience to the customers who must then take their vehicle to a remote dedicated bodyshop facility, but is also a loss of custom for the local workshop. Furthermore, such facilities are not mobile making it impossible to take such a repair and paint service to the customer, that is to provide a mobile repair and paint service. Without containment of paint or primer fumes, vapours or particulates produced during spraying and/or curing, such fumes vapours or particulates would enter the atmosphere leading to environmental pollution and the breathing of hazardous chemicals by the operator. Furthermore, contaminates such as dust and insects could be entrained therein, leading to a poor finish. Due to the limitations of the present systems government regulations concerning painting are often flouted with subsequent health and safety issues arising.
It is an object of the present invention to provide an extraction system which overcomes or alleviates the above described drawbacks.
In accordance with a first aspect of the present invention there is provided an extraction system comprising a containment unit with means to enclose a selected area on a surface of an object to the sprayed and/or dried, the unit having an outlet which is connectable to an extraction unit and an inlet connectable to an air source. This has the advantage that localised spraying and for drying can take place within the containment unit with any overspray and/or fumes being extracted to the extraction unit. This enables spraying and drying to take place outside the confines of a spraybooth or limited finish workstation, since only the area which is being sprayed and/or dried is confined.
The extraction system may comprise at least one flexible duct connectable between an inlet of an extraction unit and the outlet of the containment unit. This has the advantage that the duct enables movement between the extraction unit and the containment unit, enabling the containment unit to be selectively located at a position remote from the extraction unit. The extraction system may include a moveable mounting for the duct. This will enable further flexibility in the placement of the containment unit.
The extraction system may comprise an extraction unit which may comprise at least one of an inlet, an extraction pump adapted to draw fluid into the extraction unit through the inlet, a filter adapted to remove particulate and hazardous contaminates from the fluid, and an exhaust to expel cleaned fluid into the atmosphere. The extraction unit may additionally include a removable container to collect said removed contaminates and particulates.
The extraction unit may be mobile. This enables the extraction system to be used outside the confines of a workshop.
The containment unit may include at least one deflector.
The containment unit inlet may form an opening to the containment unit and may enable direction of a spray from a spray gun and/or aerosol into the containment unit. The deflector may be provided about the inlet. The deflector may include a movable shield, which may be located at least partially over the containment unit inlet any may be located adjacent said containment unit outlet.
The containment means may include a frame and the enclosing means may be a flexible media. The flexible media may comprise means to enable its attachment to at least one of the surface of the object to be sprayed and/or painted or the frame. The flexible nature of the media enables the containment means to be readily adapted to enclose a variety of different sized surface areas.
The flexible media may be replaceable and may be in the form of flexible sheeting, the attachment means may be in the form of adhesive tape.
The extraction system may comprise a curing unit.
The curing unit may comprise a light source to effect curing of a painted surface. The light source may be an ultraviolet light source and/or infrared light source. The curing unit may be adapted to fit into said containment unit inlet. The curing unit may have means to seal the inlet to contain the light from the source within the enclosure. This has the advantage that light from the light source does not leave the containment unit preventing damage by fugitive rays to operators' and bystanders' eyes. Furthermore the curing operation may give rise to hazardous gas which can be readily extracted via the extraction unit.
The curing unit may have cooling vents to enable air to enter the containment unit, this enables replacement of air extracted. The cooling vents may be shielded to prevent leakage of light from the unit.
In one embodiment the extraction system may comprise a forced air supply which may be heated. The forced air supply may be provided on an articulated arm to enable its accurate placement.
In accordance with a second aspect of the present invention there is provided a method of fluid extraction comprising the steps of enclosing a section of a surface to be sprayed and/or cured and/or dried within a containment unit and extracting fluid from the containment unit using an extraction unit.
In a preferred embodiment the method includes the step of spraying within the containment unit the said surface with a paint and/or primer whilst at the same time extracting fluid from the containment unit.
In a further preferred embodiment the method includes the step of drying or curing a painted surface within the containment unit at the same time as extracting said fluid.
The method may comprise the step of filtering said extracted fluid to remove particulate and/or contaminates.
The method may include the step of deflecting said spray within the containment unit.
By spraying within the containment unit dust and/or insects are not entrained within the spray leading to a smoother/cleaner finish. Furthermore any overspray, or fumes created are contained and safely extracted with the fluid, thereby not polluting the atmosphere or creating a breathing hazard for the operator. Also since only the area that is being painted is enclosed the unit can be small and rendered portable and usable in a confined space:
The method may include the step of heating air within the containment unit prior to spraying. This has the advantage of creating a warm air environment prior to application of paint materials. Compliant coatings, waterbourne base coat and ultra high solid top coats cannot be effectively applied if the temperature is below 15° C. This enables repairs to be carried out in unheated buildings and outdoors when the temperature is low, by creating an idea environment for the application of a particular material. Additionally by applying the heat prior to the application of a further coating, it is possible to dry or flash-off the presently painted surface.
By way of example only, specific embodiments of the invention will now be described, with reference to the accompanying drawings, in which:—
In a first embodiment of extraction system 2, as best illustrated in
The hood 6 is adapted to contain a selected area to be resprayed and in use paint is sprayed into the hood 6 on to the selected area, whilst the extraction unit 4 sucks air from the hood 6 via the duct 8. The interior of the hood 6 is designed to provide an aerodynamic foil which retains over-spray for extraction with the air from the hood 6. The system comprises a filter for removing hazardous gases and particulates from the extracted air, before the cleaned air is then released into the atmosphere via exhaust flue 12 of the extraction unit 4.
As best illustrated in
The H-shaped stand 12 comprises two spaced apart parallel bars 12a, 12b interconnected by a cross-bar 12c. The vertically extending mast 14 is mounted to the cross bar 12c. The parallel bars 12a, 12b are provided with swizel castors 28, which enable the stand 12, 14 to be manoeuvred to a selected location such as a vehicle, a panel of which requires respray. The orientation of the hood 6 is then adjusted in order for the hood 6 to contain the panel or area requiring respray (which will be described further hereinunder). Each end of the parallel bars is provided with a moulded rubber bumper 30 which prevents damage to the wheels of the vehicle, in the instance that the stand is accidentally manoeuvred into the tyre. Furthermore the height of the stand 12 is such that the parallel bars 12a, 12b can be manoeuvred, at least partially under the chassis of the vehicle, enabling the hood 6 to be placed for example on a top surface of the vehicle, such as the hood or roof. The parallel bars 12a, 12b are spaced apart at a distance which enable them to straddle the width of the wheel.
The mast 14 additionally carries a spray gun connection pipe 32 extending from a filter regulator 34. The filter regulation 34 has for example a maximum pressure setting of 1.5 bar to ensure correct air pressure for atomisation of paint materials within the hood. In use a spray gun is attached to the free end of the spray gun connection pipe 32.
The hood 6 is a heavy duty plastics moulded design edged with a soft rubber strip to protect vehicles during use. In the illustrated example the hood 6 has a substantially rectangular outer frame 36 surrounding a through opening 38, the said hood opening 38 providing access into the containment zone created by the hood 6 for a spray gun. The hood 6 is provided with an outlet 40, which is connectable to the flexible ducting 8. The outlet 40 is connected to the hood opening 38 via an internal cavity 4 (as best illustrated in
The flexible ducting 8 connecting the hood to the extraction unit 4 is provided with a quick release coupling 46 to enable its connection to the outlet 40 of the hood 6. The ducting 8 is constructed from a galvanised steel helix, which provides the ducting with strength and flexibility. The ducting 8 is coated with a PVC beading to protect vehicles from accidental damage when moving the ducting around the workshop.
The opposite end of the ducting 8 is connected to the extraction unit 4. The extraction unit 4 is provided with an extraction fan (not illustrated) in the form of a centrifugal type unit which develops high pressure to overcome system resistance, and also has a motor and a control unit. Down stream of the extraction fan the extraction unit 4 is provided with a secondary stage filter in the form of a filter bag which removes residual particles from the air stream which remain after primary filtration in the hood. This protects the components of the extraction unit from contamination, and hence prolongs the life of the extraction unit 4 and reduces maintenance costs.
The extraction unit 4 is additionally provided with a low airflow indicator and an alarm. The low airflow indicator monitors the suction of the extraction unit 4 and if it drops below a preset value, which would indicate that one or more of the filters are blinded and thereby require changing, the low airflow indicator is adapted to trigger the alarm to provide a visual and/or audible signal that the filter(s) needs changing.
The extraction system 2 is operated as follows:
As best illustrated in
Access to the area to be repainted is provided through the opening 38 in the hood 6.
As best illustrated in
The frame 36 is provided with overhanging shoulders 68 which extend inwardly across the hoods opening 38, these shoulders 68 provide additional deflection surfaces, to increase containment. One of the shoulders 68a located adjacent the point of extraction 42 provides a larger defection surface in this region. This is because close to the point of extraction 42 there is more disruption created and the resultant turbulence can deflect more material 62 upwards at this region. The remaining shoulders 68 of the frame 3b create a further surface area to deflect and thereby contain any excess material.
In a second embodiment of extraction unit as best illustrated in
In a second embodiment of extraction system as illustrated in
It is to be understood that the hood 6 can be of any shape and/or size and that the deflection shoulders could be omitted, or the deflection surfaces could be adjustable. Also a variety of different hoods could be provided with each extraction unit 4, by this means a suitably sized and shaped hood can be selected for the area requiring repainting. Alternatively the hood can have adjustable sides. Likewise the curing unit could be adapted to provide a fit to a variety of hoods. A plurality of curing units could be provided each having a different curing system, such that a means of curing most suitable to the type of paint to be cured can be selected. Alternatively a plurality of different curing means may be provided within a single unit. Although the curing unit has been described as fitting into the opening, other arrangements could be envisaged, for example the curing unit could be fixed in the containment unit. Whilst a manual adjustment of the position of the hood as been described, the stand and mast could be provided with pneumatic means to power the adjustment of the orientation of the head.
Although a fixed extraction unit has been described, other forms of extraction unit could be used for example a mobile extraction unit on wheels. The extraction unit could be provided with a containment unit to collect the extracted contaminants for safe disposal. In a third embodiment of extraction system as best illustrated in
It is to be understood that although the duct has been described as being moveably mounted to a rail, the duct may be fixed directly to the filtration and extraction unit.
Although the enclosure has been described as being formed by the attachment of a flexible sheeting to the hood by means such as masking band, other forms of attachment could be used such as for example masking tape or Velcro™. Also, the hood could alternatively include a flexible skirt with magnetic means to enable its attachment to metallic surface of an item to be repaired, thereby dispensing with the need for separate sheeting. Although the hood has been described as being constructed of a heavy duty plastics material, it could be constructed from other materials.
Although vehicles have been specifically described it is to be understood that other items requiring spraying and for drying are included such as garage doors, furniture including garden furniture, fencing and appliances requiring repair.
In a fourth embodiment of extraction system 2 as illustrated in
In use the tyre 106 of a wheel whose hub 90 requires respray is deflated and placed over the inlet 94 of the extraction unit 4 such that its sealing ring 92 contacts the tyre 106 or the wheel. The hood 6 is then placed over the wheel by initially placing the masking ring 98 about the exposed hub 90 surface by fitting its inwardly extending shoulders 104 under the rim 106 of the hub 90, as best illustrated in
The system is operated by switching on the extraction unit 4 which draws air into the hood 6 opening 38 down through the hood 6, through the aperture provided in the hub 90, into the extraction unit 4. The hub 90 is sprayed by spraying into the opening 38 of the hood 6, with the overspray being contained as in previous embodiments by deflection by the effective aerofoil created by the internal surfaces of the hood. The operation of the extraction unit 4 helps to provide an air tight enclosure about the hub 90, whilst the masking rings 96 shoulders 104 protect the tyre 106 from the paint spray.
The masking ring 98 is adjustable in that is annular shape is created by a strip which is overlapped with a sliding fit, with the degree of overlap being adjusted to alter the size of the central aperture 102 to best fit about the rim 106 of the particular hub 90. The fume ring 96 has a greater outer diameter 108 than that of that of the masking ring 98, in that it always overlaps its outer edge of the masking ring 96 regardless of the size its diameter is adjusted to.
A curing unit and/or heating unit can be inserted into or adjacent to the opening into the hood to facilitate curing and/or drying as per the previous embodiment.
Although the base has been described as the extraction unit, the base could merely provide an inlet to the extraction unit which unit may be provided remotely and connected thereto by ducting.
The invention is not restricted to the above described embodiments and many modifications and variations will readily occur to one skilled in the art.
Number | Date | Country | Kind |
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0502560.6 | Feb 2005 | GB | national |
0522466.2 | Nov 2005 | GB | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/GB2006/000431 | 2/8/2006 | WO | 00 | 3/2/2009 |