EP2163316A1

EP2163316A1 - Equipment for spray gun and/or small part washing

Info

Publication number: EP2163316A1
Application number: EP09011548A
Authority: EP
Inventors: Venturato
Original assignee: Vemec Srl
Current assignee: Vemec Srl
Priority date: 2008-09-12
Filing date: 2009-09-09
Publication date: 2010-03-17
Also published as: ITPD20080262A1

Abstract

Equipment for washing spray guns and/or washing small parts which has a casing (36) assembled under the grid base plate (35) of the washing area, where casing (36) is loaded with one or more filter units (34) collecting all washing and rinsing water or washing liquid, and working as a fraction separator (7), and said washing water is eliminated by evaporation.

Description

It has always been the case that after spray guns have been used they need to be washed to remove any trace of residual paint, so that when they are used again they operate efficiently and correctly.
Currently paints are used whose solvent is water, therefore washing in this case is carried out with clean water or with a detergent. Where the paints have a thinner as a solvent, the cleaning liquid will be an appropriate solvent.
On the market there are both simple and complex devices for washing spray guns and their components, which are also protected by specific patents.
In said market devices washing can be done manually or automatically.
In the manual system, washing takes place by means of a brush fed by pressurised water or solvent or by a gun with a nozzle; in the automatic system the spray guns and their components are hit by a spray coming from appropriately positioned nozzles, so that all the parts of the above-mentioned objects are reached.
The washing devices on the market are quite elaborate and the volume of water (or another liquid) used is quite large; and the cost for disposing of the used water as a special waste is quite large.
The water to be used is taken from a tank by means of a pump; or with the ejection system according to the Venturi principle.
The dirty water is collected, treated with a coagulant for the flocculation of the paint particles and filtered, to then end up in the water tank to be re-used as clean water.
Said water, after a series of uses, even if filtered, stops being clean and starts to smell, and needs to be disposed of as a special waste by specially authorised companies.
As we might imagine, both the structural complexity of the device for washing that is available on the market and the amount of polluted water that is created are quite expensive to dispose of.
The aim of this patent is to create equipment for washing spray guns and their components and/or small parts that are soiled with paints and the like, one that is extremely simple, with water (or another liquid) consumption that is practically insignificant, to be eliminated preferably through an evaporation process, thereby avoiding the problem of disposing of the dirty and polluted water (or another liquid) considered special waste to be disposed of by authorised companies with consequent high costs.
The equipment for washing spray guns and their components and/or small parts is contained in a C-shaped casing and basically has three parts.
The lower part where the fraction separator is, the intermediate part where the zone for the washing operations is, and the upper part where the system for supplying the pressurised water (or another liquid) or air is, for feeding the devices used by the operator that cleans the spray guns.
The fraction separator can be removed and is composed of a sort of tank with a sealed bottom.
Near the bottom of the tank there is diamond-tipped grid. Above said diamond tipped-tipped grid is a layer of filters (which can be one or more paper cloths with an appropriate shape and structure).
Above the filters there is a flat grate that holds all the filters and its surface is the flat surface that establishes the washing area.
The lower part of the washing area is marked off by the flat grid of the fraction separator.
The spray guns and/or other small objects to be washed are placed on said grid.
Inside the washing area there is a gun with a brush that uses water (or another solvent liquid), with a detergent if required, for washing the outsides of the pieces, and a gun with a nozzle for washing the insides (with water or solvent and any detergent) with water or solvent (and with air).
Said guns are fed by tubes that come out of the compartment of the washing area.
Likewise on the top cover surface there is an outlet for clean water for rinsing and an air outlet for drying and an outlet like for a shower.
The lower surface of the upper part of the equipment makes up the upper limit of the washing area.
In the upper part there are the paths of the various tubes, valves and switches and everything else regarding the pneumatic system connected externally with the water mains (and/or a solvent or water tank) and with the compressed air system. Said pneumatic system supplies the guns and the nozzles and the sprayers in the washing area with water or solvent through tubes.
For cleaning the spray guns, once the equipment is activated with water or with the solvent and with pressurised air, the operator works on the spray gun to be cleaned using a gun with a brush (using water or solvent) and using the gun with a nozzle fed with water or a solvent, and then pressurised air. At the end the washing is completed with rinsing and blowing.
During the whole cleaning operation the dirty liquid and the rinsing liquid (in all at most about ¼ of a litre) falls onto the filtration units of the fraction separator underneath.
The absorption capacity of the separator is about 2 litres.
Once the absorption capacity of a separator is exhausted, it is replaced with a new one. The used one can be put in a place that favours the evaporation of the water or solvent fraction in it (for example in an oven during the drying of the paint applied to cars). In this way the separator can be used again for another spray gun washing cycle replacing, if necessary, just the first or just the first two filtration units if these have a lot of dried paint on the surface that hinders the passage of the liquid to the underlying units.
With the washing equipment described in this patent there is no dirty water (or solvent) that specialised companies need to dispose of, because the little water (or solvent) that is used is eliminated through evaporation.
The filter units that are soiled with dry paint are disposed of when they are no longer permeable, adopting the same disposal procedure as the masking paper that is used by the body repair worker in painting the cars.
What has been previously described can be seen clearly in the attached drawings.

Fig. 1 shows the casing seen from the side and fixed to a load-bearing wall where the lower casing is identified by a series of removable drawers, each one regarding a fraction separator, in the middle the washing chamber equipped with guns and apparatus for rinsing, and on the top the pneumatic system for supplying water and air for the washing cycle.
Fig. 2 shows the casing of fig. 1 resting on a surface using feet applied to the base.
Fig. 3 is an axonometric view of the casing of figs. 1 and 2 and a special base suitable for supporting it.
Fig. 4 is an axonometric view from above of the casing showing the operating controls and the air and water pressure gauges on the front of the top part.
Fig. 5 is an axonometric view of the casing showing the surface beneath the upper part of said casing from which the air pressure regulators emerge and from which the various connections for operating with water and air emerge.
Fig. 6 is a schematic of the pneumatic system with relative connections for water and air with shut-offs, with the switches for supplying air and water to the equipment used by the operator for washing, and for the various rinsing systems.
Fig. 7 shows a switched off gun with a brush for washing being gripped by an operator.
Fig. 8 shows an inactive gun with a nozzle for washing being gripped by an operator.
Fig. 9 shows an inactive water gun fitted with a nozzle fitted to the spray gun for cleaning its interior.
Fig. 10 is an enlargement of the nozzle gripped by the spray gun of fig. 9.
Fig. 11 shows the operation for rinsing the spray gun with a spray.
Fig. 12 shows the operation for blowing the spray gun with air.
Fig. 13 shows the rinsing of the spray gun with a shower of liquid.
Fig. 14 shows the liquid pouring onto the filter units of a fraction separator following the cleaning of a spray gun using a gun with a brush and a gun with a nozzle.
Fig. 15 is a section view of an enlarged portion of a fraction separator where the we can see the bottom of the container, the grid removed from the bottom that supports the filter units, the filter units and the upper flat grid that keeps the filter units compact.

We should remember that in the fraction separators, instead of the filter units composed of sheets of paper other absorbent materials can be used like sawdust, cellulose wadding and any other material with the required absorption characteristics, in terms of both quality and quantity.
To clean spray guns or other small pieces you proceed as follows.
Having installed the casing of the equipment 1 by fixing it to a load-bearing wall or by placing it on a flat work surface 4 or by placing it on the special base 3, the pneumatic system 17 is connected to both the air line 18 (not drawn) and the water line by inserting the washing tube into its housing (not drawn) and by inserting the rinsing tube into another housing (not drawn).
Once the pneumatic system has been connected the control 8 is opened on the front panel 6 of the upper box section part 5 where the pneumatic system 17 is located.
Use the pressure regulators 13, 14 until the gauges 8, 19 indicate the programmed pressure (preferably 3 - 3.5 bars).
The operator, having taken the spray gun 29 to be washed, activates the valve switch 11, presses the trigger of the brushgun 20, 24 until a steady flow comes out for cleaning the outside.
Then the operator pulls the trigger of the gun 19, 24 that has a nozzle 27, 28.
Once the operator has activated the valve switch 12, he then rinses with a spray 30, with a shower flow 31, and with air 32.
All the liquid (washing and rinsing) used for the entire cleaning cycle, when it falls 33 onto the flat grid 35 of the fraction separator 7, is absorbed by the filter units 34.
To change the used up fraction separator 7 once the absorption capacity of the filter units 34 supported by the diamond-tipped grid 37 is used up, when drips start to fall onto the bottom of the tray 36, it is replaced with a new one taken from the spares in the drawers 38 on the base of the casing 1.
At this point we should remember that in the description above the cleaning liquid is generally considered to be water (maybe with some detergent added) if the paints used by the spray guns to be cleaned were the water type, but if the paints used by the spray guns to be cleaned were solvents other than water, then also the cleaning liquid for washing would have been other than water. Therefore in the above description of the washing cycles in place of the word "water", we should read "washing liquid".
After what has been explained above, in addition to originality, there is the distinctive inventiveness of the invention that revolutionises an already consolidated system in the specific field of the cleaning of spray guns and/or small parts, where the existing equipment on the market is complex and costly and creates dirty liquid that needs to be disposed of as a special waste at a high cost. With the equipment described in this patent, the washing and/or rinsing water is eliminated by evaporation and the few filter units covered by dried paint are disposed of as an entirety and with the same masking paper disposal system that the body shop workers use when they are painting vehicles.

Claims

Equipment for washing spray guns and/or small parts, characterised by the fact that it has a casing (36) assembled under the grid base plate (35) of the washing area, where casing is loaded with one or more filter units (34) collecting all washing and rinsing water (or washing liquid) and working as a fraction separator (7).
Equipment for washing spray guns and/or small parts, according to claim 1 characterised by the fact that the above-mentioned fraction separator (7) can be removed and replaced with new a one (38) once its absorption capacity is exhausted.
Equipment for washing spray guns and/or small parts, according to claim 1 or 2 characterised by the fact that the fraction separator (7), having been removed upon exhaustion of its absorption capacity, will be ready to be used for a new washing cycle once the water (or liquid) in it has fully evaporated.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims, characterised by the fact that said fraction separator (7), including its various filter units (34), can be used for more than one spray gun and/or small parts washing cycle, by replacing just the first or first two filter units in the event the filtering capacity is impaired due to dry paint covering the surface of the two fraction units mentioned above.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims characterised by the fact that the fraction separator (7) is made up of a water- and airtight bottom tray (36), also including a diamond-tipped grid (37) at a slight distance from the bottom, a series of filter units (34) being placed above said diamond-tipped grid, and a flat grid (35) positioned over the filter units (34) that besides keeping the filter units (34) close one another also serves as a flat surface for washing tools and small parts.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims characterised by the fact that the filter units (34) are made up of special absorbent paper cloths.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims characterised by the fact that the filter units (34) can be sawdust, cellulose wadding or any other material that has the same absorption and fractional power as that of the absorbent paper cloths.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims characterised by the fact that the filter units, which have been removed from the filter unit pack (34) in the fraction separator (7) because they are soiled with paint and lacking in filtering power, are disposed of with the same method used for the removal of the dirty masking paper used, for example, by body shop workers during car painting operations.
Equipment for washing spray guns and/or small parts, according to one or more of the previous claims characterised by the fact that the washing and rinsing water (or washing liquid) in the fraction separator (7) are disposed of either through spontaneous evaporation or by means of heating devices or by placing the separator (7) filled with water or liquid into the painting cabins during car painting operations.