WO2014037749A1

WO2014037749A1 - Spray gun washing apparatus and method

Info

Publication number: WO2014037749A1
Application number: PCT/GB2013/052359
Authority: WO
Inventors: Anthony PLANT; Michael Nicholas
Original assignee: REVELHOLME MARKETING Ltd
Current assignee: REVELHOLME MARKETING Ltd
Priority date: 2012-09-07
Filing date: 2013-09-09
Publication date: 2014-03-13
Anticipated expiration: 2015-03-07
Also published as: GB201216027D0; GB2505692A; GB2505692B

Description

Title: Spray gun washing apparatus and method Description of Invention

This invention relates to an apparatus and method for washing a spray gun.

After use of a spray gun, e.g. a hand-held spray gun used for spraying paint, generally it is necessary for the spray gun to be washed thoroughly. It is important that when a paint spray gun is not being used, none of the paint which has been sprayed remains in the spray gun where it can harden and cause partial or complete blockage of passages in the spray gun. If a paint spray gun is subsequently to be used to spray paint of a different colour from that for which it was previously used, the previously-used paint must be removed to ensure no contamination of the subsequently-used paint which may interfere with the colour effect produced. Washing to prevent clogging and/or contamination may also be necessary when spray guns are being used for spraying liquids other than paint, e.g. glues, inks, varnishes, etc.

A typical hand-held spray gun for whose washing the invention has been devised comprises a body with a handle part by which it may be held. The body carries a spray nozzle, and a container for the paint or other substance to be sprayed is connected atop the body so that the paint may flow therefrom to the nozzle through one or more internal passages in the body. Compressed air is supplied to the spray gun through a flexible hose, and the hose typically connects to the handle part of the gun. An operating trigger is provided, arranged to operate a valve or valves by which the supply of air through one or more passages in the body and handle, and the supply of the substance to be sprayed, to the spray nozzle, can be started and stopped as required. A particular embodiment of spray gun having the above features is described and illustrated hereafter but it is to be appreciated that the present invention is usable for washing spray guns of other configuration.

It is known to carry out spray gun washing by supporting a spray gun in a chamber or tank within which a number of nozzles are disposed for directing a washing liquid in jets or sprays towards parts of the spray gun. In the case of a spray gun used for spraying paint, the washing liquid usually is a solvent of an appropriate type depending on the nature of the paint which is being sprayed. The nozzles for washing liquid include one which directs the washing liquid into the spray nozzle part of the spray gun through the passage through which the liquid to be sprayed is delivered from its container to the spray nozzle of the gun. This is the most important part of the spray gun for washing, and it will be appreciated that for effective washing the spray gun has to be carefully positioned in relation to the washing liquid nozzles so that the washing liquid is directed to the appropriate part of the spray gun.

One way in which this problem of spray gun positioning in washing apparatus has been approached is for the spray gun to be supported in the washing chamber by a support member which engages the spraying liquid-receiving part of the spray gun, e.g. by a screw threaded connection, the support member itself affording a passage for delivery of the washing liquid. Typically the support member extends upwardly with the spray gun supported at its upper end in an inverted orientation compared with its usual general orientation in use. However, this is inconvenient to use and may even cause damage to the spray gun.

A further approach to the problem of supporting a spray gun is disclosed in WO 201 1 /105953, wherein a spray gun is supported in a washing space by holding it to an attachment surface by magnetism, so that the spray gun's position is variable depending on the position on the spray gun of its paint inlet, relative to the position of the nozzle delivering washing liquid. However, this also is inconvenient to use.

With the object of addressing the above difficulties, according to one aspect of the present invention we provide apparatus for washing a spray gun, comprising:

a washing chamber;

a support for supporting a spray gun in the chamber;

means for supplying washing liquid to the interior of the chamber, including a liquid delivery nozzle for co-operation with a spraying liquid inlet of the spray gun;

wherein the support and the liquid delivery nozzle are movable relative to one another within the washing chamber, to permit engagement between the nozzle and the spraying liquid inlet of a spray gun supported by the support; and there is means for urging, in use, the nozzle into engagement with the liquid inlet of the spray gun.

The urging means may comprise biasing means. The biasing means may include spring means operable on the nozzle and/or the support. Either or both of the delivery nozzle and the spray gun support may be movable under the influence of a biasing spring operative between the movable part and a stationary part of or associated with the washing chamber. Alternatively a biasing spring may be operable between the delivery nozzle and spray gun support.

The means for supplying washing liquid to the interior of the chamber may include a plurality of liquid delivery nozzles to deliver washing liquid to a number of positions within the chamber, to wash other parts of a spray gun in addition to the spraying liquid inlet thereof. Liquid delivery nozzles may also be arranged in the washing chamber to wash other spray gun parts suitably supported within the chamber, e.g. a paint container, detachable components (e.g. spray nozzle components) of a spray gun.

The support for the spray gun may be of any suitable form. Conveniently, it comprises a member with respective portions engagable with a handle part and with a body part of the spray gun adjacent its spray nozzle/spraying liquid inlet region.

The support may support the spray gun in an orientation with its handle extending generally downwardly from its body and with its spray nozzle inclined downwardly so that its spray nozzle region is at a lower disposition than a body part adjacent the handle.

The support may be mounted relative to the washing chamber by at least one upstanding mounting member. There may be two such mounting members, and each may incorporate a biasing spring.

According to a second aspect of the invention, we provide apparatus for washing a spray gun, comprising:

a washing chamber;

a support for supporting a spray gun in the chamber;

wherein the support and the liquid delivery nozzle are movable relative to one another within the washing chamber, to permit engagement between the liquid delivery nozzle and the liquid inlet of a spray gun supported by the support; and there is means for causing relative movement between the support and the liquid delivery nozzle for urging, in use, the nozzle into engagement with the liquid inlet, wherein the means for causing relative movement comprises biasing means. The second aspect of the invention may have any of the optional features of the first aspect of the invention.

According to another aspect of the invention, we provide a method of washing a spray gun, preferably including use of a washing apparatus according to the first or second aspects of the invention.

According to a further aspect of the invention we provide a method of washing a spray gun, comprising supporting the spray gun in a washing chamber, and supplying washing liquid to the interior of the chamber through at least one liquid delivery nozzle to wash the spray gun, the at least one liquid delivery nozzle including one adapted to co-operate with a spraying liquid inlet of the spray gun;

wherein a support for a spray gun in the chamber, and the liquid delivery nozzle co-operable with the liquid inlet of the spray gun are movable relative to one another within the chamber;

and the method comprises urging the co-operable liquid delivery nozzle into engagement with the liquid inlet of the spray gun using a biasing means. The invention is advantageous in that it is readily usable with spray guns of differing size and/or configuration.

The invention will now be described by way of example with reference to the accompanying drawings, of which:

Figure 1 is a diagrammatic view of a first embodiment of spray gun washing apparatus in accordance with the invention;

Figure 2 is an enlargement of part of figure 1 ;

Figure 3 is a view, as figure 1 , of a further embodiment of the invention;

Figure 4 is an enlargement of part of the embodiment of figure 3. Referring firstly to figures 1 and 2 of the drawings, a spray gun with whose washing the invention is concerned is seen most clearly in figure 2. The spray gun (10) comprises a body 12 having at one end a spray nozzle indicated generally at 14. At the opposite end of the body 1 2 a handle 16 extends downwardly from the body (when spray gun is oriented in the position in which it is intended to be, and normally is, used). The lowermost end of the handle 16 has a fitting for a flexible compressed air hose to be connected to it as indicated at 18, to power the spray gun. An operating trigger 20 is pivotally connected to the body 12, and extends to a position in which it is operable by a user, utilising one or two fingers to pull the free end of the trigger 20 towards the handle 16 and thereby, through an operating rod 22, operate a valve within the body 12 to open a passage extending through the handle and body from the air hose fitting 18 to the spray nozzle 14 of the spray gun. A liquid which is to be sprayed, e.g. paint, is supplied to the spray gun from a container, not shown, which is attached to the body 12 of the spray gun at a mounting surface region 24 adjacent the nozzle 14. The region 24 of the spray gun body is provided with, for example, a screw-threaded bore by which the liquid container may be attached above the body 12 of the spray gun, to deliver the liquid to the spray nozzle 14 through an internal passage. The trigger 20 also controls flow through this passage. When the spray gun is operating, the liquid being sprayed flows to the spray nozzle under gravity assisted by the flow of air through the spray nozzle, so that the liquid is sprayed from the spray nozzle in a predetermined pattern. Spray nozzle arrangements for spraying liquid, designed to suit the particular viscosity of liquid which is being sprayed, are, of course, well known. The body includes a hook portion 26 so that the spray gun, with liquid container attached, can be hung up in a generally upright orientation as illustrated, when temporarily not being used for spraying. The washing apparatus comprises a washing chamber 30 which is a box-like container having a base 32, upstanding walls 34 and an openable lid or cover 36 to give access to the interior of the washing chamber. As illustrated, the washing chamber is supported on a base unit indicated generally at 38, which is provided, in a manner generally known for spray gun washing apparatus, with one or more containers 40 for washing liquid, as well as one or more pumps (41 , figure 3), filters, and other components which provide for supply of the washing liquid to a number of liquid-delivery devices within the washing chamber 30, and for recovery of the washing liquid from the washing chamber 30.

The washing chamber 30 is provided with a washing platform 42 spaced above its base 32, and the washing platform 42 carries a support indicated generally at 44 for the spray gun 10. The support 44 comprises a metal support component having a base part 46 and long and short limbs 48, 50 extending upwardly and at a diverging inclination from the base part 46. The limbs 48, 50 have respectively a semi-circular cut out and a slot extending into them, from their free ends towards the base part 46 of the support, so that a spray gun may be carried thereby by being held in the respective formations at the free ends of the limbs 48, 50.

The support component 44 of the support is carried relative to the washing platform 42 by two spaced support pillars 52, 54. Each of the support pillars 52, 54 comprises a first part 56 upstanding from the platform 42 in telescopic assembly with a second part 58 extending downwardly from the base part 46 of the component 44, a compression spring being disposed within the part 58 and abutting the top of the upstanding part 56 so that the support component 44 is spring biased upwardly relative to the platform 42. The washing chamber 30 is provided internally with a number of liquid outlet jet or spray nozzles supplied with washing liquid pumped from the containers 40 thereof, for washing a spray gun supported within the chamber as above described. Figure 1 of the drawing shows three spray nozzles 62, 64, 66 at the end of respective pipes extending from a liquid supply manifold 68. A further spray nozzle 70 is provided on the platform 42, spraying upwardly therefrom in opposition to the spray nozzle 62. The nozzles 62, 70 are for washing a paint container 72 inverted on the platform 42. The nozzles 64, 66 are directed generally downwardly towards the spray nozzle end and opposite end of the body 12 of the spray gun. The manifold 68 further supplies a downwardly extending pipe 74 at whose lowermost end there is a frusto conical downwardly-pointing outlet nozzle 76 which is arranged to enter the upwardly-facing internally screw threaded bore provided in the mounting portion 24 of the spray gun body 12. This provides for washing of the passage within the body 12 which conveys the liquid being sprayed to the spray nozzle 14.

If a spray gun is to be washed using the above-described apparatus, the spray gun will have its container for the liquid being sprayed removed, and be disconnected from the compressed air hose by which the gun is powered. A clip, e.g. of wire or any suitable material will be applied to the handle 16 and trigger 20 of the spray gun, as indicated at 80, to hold the trigger in the "on" position, i.e. with the valves controlling the air and liquid supply passages to the spray nozzle 14 open. The spray gun is placed in the support member 44, the latter having being moved downwardly towards the platform 42 against the action of springs 60 to enable this to be done. When the support 44 is no longer depressed, the springs 60 urge it and the spray gun held thereby upwardly, so that the washing liquid outlet 76 engages in the bore in the mounting part 24 of the spray gun. With the lid 36 of the washing chamber closed, the pump 41 may be operated to cause discharge of the washing liquid through the respective outlet nozzles therefore, thoroughly to wash the spray gun of the liquid which has been sprayed. A possible modification of the construction of the washing apparatus is depicted in figures 3 and 4. In this embodiment, wherein like reference numerals are used for parts corresponding to those above described in relation to figures 1 and 2, the supporting posts 52, 54 for the support 44 are not spring-biased, so the support 44 is fixed in position relative to the washing platform 42. Instead, an assembly comprising the pipe 74 and its outlet nozzle 76, and outlet nozzles 64, 66 and their supply pipes, is spring-biased downwardly by a spring arrangement 90 provided in the upper part of the washing chamber. A manifold 68 supplying the nozzle 64, 66, 76 may be supplied with washing liquid through a flexible pipe.

In yet a further embodiment, spring means for biasing the support 44 and a spray gun held thereby, relative to the washing liquid delivery nozzle 76, may be operative between the former and the latter rather than between either of them and stationary parts associated with the washing chamber. Again, a flexible pipe for supply of washing liquid to the manifold 68 would be utilised.

In yet a further embodiment, instead of utilising a biasing spring or springs to cause the relative movement between the support 44 and nozzle 76 which urges the latter into engagement with the liquid inlet of the spray gun, the support and/or the nozzle may be movable manually relative to a, or a respective, mounting component. Such a mounting component may be provided with a guideway formation enabling sliding adjustment of the support or nozzle as the case may be, the slidable component possibly having a handle or other formation to facilitate its movement. A locking means may be provided to hold the slidable component in its position thus established.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components. The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1 . Apparatus for washing a spray gun, comprising:

a washing chamber;

a support for supporting a spray gun in the chamber;

wherein the support and the liquid delivery nozzle are movable relative to one another within the washing chamber, to permit engagement between the liquid delivery nozzle and the liquid inlet of a spray gun supported by the support; and there is means for causing relative movement between the support and the liquid delivery nozzle for urging, in use, the nozzle into engagement with the liquid inlet, wherein the means for causing relative movement comprises biasing means.

2. Apparatus according to claim 1 wherein the biasing means includes spring means operable on the liquid delivery nozzle and/or the support.

3. Apparatus according to claim 2 wherein the delivery nozzle is movable by a biasing spring operative between it and a stationary part of or associated with the washing chamber.

4. Apparatus according to claim 2 or claim 3 wherein the spray gun support is movable by a biasing spring operative between it and a stationary part of or associated with the washing chamber.

5. Apparatus according to claim 2 wherein a biasing spring is operable between the delivery nozzle and the spray gun support.

6. Apparatus according to any one of the preceding claims wherein the means for supplying washing liquid to the interior of the washing chamber includes a plurality of liquid delivery nozzles to deliver washing liquid to a number of positions within the washing chamber.

7. Apparatus according to any one of the preceding claims wherein the support for the spray gun comprises a member having respective portions engagable with a handle part of the spray gun and with a body part thereof in a region adjacent its spraying liquid inlet.

8. Apparatus according to any one of the preceding claims wherein the support supports a spray gun in an orientation with its handle extending downwardly from the body and the body inclined with its spray nozzle inclined downwardly.

9. Apparatus according to any one of the preceding claims wherein the support is mounted relative to the washing chamber by at least one upstanding mounting member.

10. Apparatus according to claim 9 wherein the support is mounted by two upstanding mounting members.

1 1 . Apparatus according to claim 9 or claim 10, as appendent directly or indirectly to claim 4, wherein the or each mounting member incorporates a biasing spring.

12. Apparatus substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

13. A method of washing a spray gun, comprising supporting the spray gun in a washing chamber, and supplying washing liquid to the interior of the chamber through at least one liquid delivery nozzle to wash the spray gun, the at least one liquid delivery nozzle including one adapted to co-operate with a spraying liquid inlet of the spray gun;

and the method comprises urging the co-operable liquid delivery nozzle into engagement with the liquid inlet of the spray gun using a biasing means.

14. A method according to claim 13, wherein the washing is carried out using apparatus according to any one of claims 1 to 12.

15. A method substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

16. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.