EP3930913A1

EP3930913A1 - Rear casing for a spray gun and spray gun comprising a rear casing of this type

Info

Publication number: EP3930913A1
Application number: EP20711050.3A
Authority: EP
Inventors: Roger TOBLER
Original assignee: Gema Switzerland GmbH
Current assignee: Gema Switzerland GmbH
Priority date: 2019-03-01
Filing date: 2020-02-27
Publication date: 2022-01-05
Anticipated expiration: 2040-02-27
Also published as: CN113423509A; WO2020178114A1; EP3930913B1; US20220080447A1; PL3930913T3; DE102019105244A1

Abstract

The invention relates to a rear casing (10) for a spray gun (1), in particular a powder spray gun (1), wherein the spray gun (1) has a handle part (2) and a gun barrel (3) connected to the handle part (2). The rear casing (10) can be removeably and exhangeably attached to the rear side of a main body (4) of the spray gun (1) and has a first region designed as a handle casing (11) and a second region designed as a covering casing (12) for rear-side covering of a rear region of the gun barrel (3). At least one connection element (14) is provided on the second region of the rear casing (10) for optionally forming a removable connection to a part having, for this purpose, at least some portions with a design complementing that of said connection element. In particular, according to the invention, the entire rear casing (10), together with the at least one connection element (14), is designed as a monolithic plastic component, in particular a plastic injection moulded part.

Description

REAR SHELL FOR A SPRAY GUN AND SPRAY GUN WITH A

SUCH REAR SHELL

description

The present invention relates generally to the technical field of

Spray coating of objects.

According to one aspect of the invention, this relates in particular to a spray gun for spray-coating objects with powdery coating material. However, the invention is not limited to this, but can also be used for

Spray guns for spray coating objects with liquid

Coating material can be used. In particular, the invention relates to an optimized rear shell for spray guns, with which the rear side of a base body of a spray gun can be covered.

Spray guns of the type considered here are already known from the prior art. For example, the document EP 0 383 030 A1 relates to a spray gun for spray-coating objects with coating powder. The spray gun known from this prior art has a handle part and a gun barrel connected to the handle part.

In the case of powder spray guns in particular, when they are used, fine powder dust is generated which can penetrate the gun in an undesirable manner. At Spray guns for liquid coating material there is a risk that atomized liquid particles will be deposited inside the spray gun. Both with powder spray guns and with liquid spray guns, there is a fundamental risk that the interfaces between the gun parts

Floch voltage creepage paths between floch voltage parts for electrostatic charging of the coating material and gun parts to be electrically isolated from it arise.

Another disadvantage of those generally known from the prior art

Spray guns can be seen in the fact that the handle parts of the spray guns are often not optimally designed in ergonomic terms. In addition, the spray guns known from the prior art have the disadvantage that they often do not have the necessary rigidity with regard to bending and torsion.

Therefore, the invention is based on the object with respect to

to remedy the problems raised.

According to one aspect of the invention, this relates to an optimized stain shell for a spray gun, the spray gun having a handle part and a gun barrel connected to the handle part. It is provided according to the invention that the stain shell can be detachably and interchangeably attached to the back of a base body of the spray gun.

The stain shell has a first area designed as a grip shell, which is designed to cover the grip body of the spray gun, in particular on the rear. Furthermore, the stain shell has a second area, designed as a cover shell, for covering the rear of a rear area of the gun barrel.

At least one connecting element is provided on the second area of the stain shell, via which, if necessary, a releasable connection can be formed with a part which is at least partially complementary thereto. According to the invention it is provided in particular that the entire rear shell, together with the at least one connecting element, is designed as a monolithic plastic component, in particular a plastic injection-molded part.

The advantages that can be achieved with the invention are obvious:

Providing a rear shell designed as a monolithic plastic component, the rear area of the spray gun and in particular the area which connects the handle part of the spray gun to the gun barrel can be made particularly rigid and torsion-resistant, which has a direct effect on simplified handling of the entire spray gun.

In addition, the one-piece rear shell ensures that the entire spray gun can be optimally sealed, since the

Interface areas through which coating material can pass are minimized.

Another decisive advantage can be seen in the fact that the first area, designed as a handle shell, is one-piece and seamless, i.e. monolithic, is connected to the second area designed as a cover shell. In this way, the handle part of the spray gun is ergonomically improved, since there are no disruptive transitions which could possibly lead to injuries to the hand of the operator of the spray gun.

According to embodiments of the present invention, the rear shell can furthermore have a transition area which acts as a handle shell

formed first area connects to the second area formed as a cover shell. In this embodiment, the transition area, together with the first area designed as a grip shell and the second area designed as a cover shell, is designed as a whole as a monolithic plastic component.

According to preferred implementations of the rear shell according to the invention, it is provided that the first area designed as a handle shell is at least partially approximately U or V-shaped when viewed in cross section and has a rear wall and two side walls integrally formed thereon. It is advisable here if the outer surfaces of the rear wall and the side walls formed thereon act as a handle shell formed first area at least in areas have a configuration adapted to increase the grip security, and in particular have a texture.

According to preferred implementations of the rear shell according to the invention, the outer surfaces of the rear wall and the wall formed thereon have

Side walls of the first area, which is designed as a grip shell, have a polygonal wave shape which is particularly adapted to the hand of the operator of the spray gun.

This embodiment is based on the knowledge that when gripping the grip part of the spray gun, the operator inevitably bends or bends the fingers of the gripping hand at least partially. Therefore, an ergonomically optimal shape of the handle part or the first area designed as a handle shell is an ergonomic polygonal wave shape in order to create a perfect grip.

Of course, however, the invention is not specific to such

Embodiments of the first area designed as a grip shell are limited.

According to embodiments of the rear shell according to the invention, at least one cable strain relief is preferably integrated in the rear wall of the first area designed as a grip shell. By the fact that with this

Embodiment, the cable strain relief is integrated in the rear shell and in detail in the rear wall of the first area designed as a grip shell, the spray gun can be made particularly compact.

With regard to the second area of the

Rear pan is in accordance with embodiments of the present invention

it is provided that this area is approximately U-shaped in cross section, at least in some areas, with a rear wall and two side walls formed integrally thereon. According to embodiments of the rear shell according to the invention, the second area designed as a cover shell furthermore has a first area designed as a handle shell at least partially or

in areas opposite to the upper wall. This upper wall is in one piece with the rear wall and the wall formed thereon

Formed on the side walls of the second area designed as a cover shell. It is advisable here for the at least one connecting part to be formed in one piece on this upper wall. A hook-shaped or eyelet-shaped element is particularly suitable as the connecting part.

According to advantageous developments of the rear shell according to the invention, there is at least one, in particular set back, opening for at least one in the rear wall of the second area designed as a cover shell

Control element and / or at least one display element of the spray gun is provided. The at least one opening is designed in particular to receive and / or embed the at least one operating element and / or the at least one display element of the spray gun in a recessed manner in order to ensure optimal protection of the operating element or the display element, while at the same time the penetration of Coating material is effectively prevented in the edge region of the opening.

Alternatively or in addition to this, it is conceivable that in the rear shell and preferably in a side wall of the second area designed as a cover shell, at least one receptacle for a switch or the like and preferably an element for actuating a switch or the like that is movably molded relative to the rear shell is formed, in particular is integrally formed.

With these developments, various functionalities can be integrated into the monolithic rear shell.

In preferred embodiments, for example, it is provided that in the rear shell and preferably in the material of a side wall of the as

Cover shell formed second area is integrated at least one electrically conductive grounding element. The at least one grounding element serves to ground a counter electrode of the spray gun or to a

To set ground potential. For this purpose, in the assembled state of the spray gun, the grounding element integrated in the rear shell can be connected via a

Earthing conductors, such as a galvanically conductive connecting web, are connected to a counter electrode arranged in the vicinity of a charging electrode of the spray gun in order to connect the counter electrode to an electrical potential which is different from the electrical potential, to which the charging electrode is connected. In this way, at least some of the free ions generated during the electrical charging of the coating powder can be absorbed via the counter electrode and the grounding element integrated in the rear shell.

The grounding element integrated in the rear shell is preferably connected in an electrically conductive manner to the grounding or a potential connection via an electrical line running in particular in the interior of the handle of the spray gun.

In order to facilitate assembly of the spray gun, it can be provided that a centering, in particular in the form of a centering tab or the like, is provided at least in some areas on the front longitudinal edge of the side walls of the rear shell. The centering is designed in particular to bring about an independent alignment of the position of the rear shell relative to the rear side of the base body of the spray gun when the rear shell is mounted on the rear side of the base body.

Alternatively or additionally, it is advantageous if at least regionally an at least regionally stepped area is implemented on the front longitudinal edge of the side walls of the rear shell and in particular in or on the end face of the front longitudinal edge of the side walls of the rear shell. In this way, an optimal seal against the back of the

Base body of the spray gun can be achieved, since a labyrinth sealing area can be formed by the stepped area.

The rear shell is on the back of the main body of the spray gun

can be plugged on, wherein, according to preferred implementations, only a single screw is sufficient to correspondingly fix the rear shell to the base body of the spray gun. This further reduces the risk of coating material penetrating into the spray gun, since only a small number of (in the best case only a single) opening for receiving a screw in the

Rear shell must be provided.

The entire rear shell is preferably designed as a monolithic component made of an antistatic plastic material. As a preferred plastic material Polyamide-12 is mentioned at this point, although others are also mentioned

Plastic materials would be suitable in principle.

The invention also relates to a spray gun with such a rear shell.

An exemplary embodiment of the present invention is described in more detail below with reference to the accompanying drawings.

Show it:

FIG. 1 shows an example schematically and in a side view

Ausfüh approximate form of the spray gun according to the invention with the optimized rear shell in the assembled state;

FIG. 2 schematically and in an exploded view the exemplary

Embodiment of the spray gun according to the invention according to FIG. i;

FIG. 3 schematically and in a first isometric view the

exemplary embodiment of the spray gun according to the invention according to FIG. 1;

FIG. 4 schematically and in an isometric exploded view the

exemplary embodiment of the spray gun according to the invention according to FIG. 3; and

FIG. 5 schematically and in a second isometric exploded view the exemplary embodiment of the invention

Spray gun according to FIG. 1.

The spray gun 1 according to the invention, as shown schematically with reference to an exemplary embodiment in the drawings, is used

in particular for applying coating material to an object (not shown in the drawings).

The illustrated embodiment of the spray gun 1 according to the invention is the coating material to be applied to the object especially electrostatically charged or chargeable

Coating powder.

It is provided, however, that a spray gun 1 constructed according to the invention can also be used to apply other coating materials instead of electrostatically charged coating powder to an object. For example, the spray gun 1 can be used to apply liquid coating materials to an object.

The spray gun 1, as it is shown schematically in the drawings, essentially has a handle part 2 and one connected to the handle part 2

Gun barrel 3 open.

The manually grippable handle part 2 has, as in particular the

Exploded views can be seen on a base body 4, which is connected to a base body 4 of the gun barrel 3.

Preferably, the base body 4 of the handle part 2 is integral with the

Base body 4 of the gun barrel 3 formed, for example as a

monolithic plastic injection molded part. In this way, an in particular one-piece base body 4 of the spray gun 1 is created.

The gun barrel 3 of the spray gun 1 has one up to one

Nozzle arrangement 6 extending first (front) area 3a and a rear second (rear) area 3b. It is provided here that the handle part 2 is arranged between the front and rear areas 3a, 3b, specifically preferably in an area in which the handle part 2 is arranged above the center of gravity of the entire gun barrel 3. This promotes the well-being of the operator of the spray gun 1 during the use of the spray gun 1, in particular over a relatively long period of time.

The base body 4 of the spray gun 1 is in particular formed in one piece from an electrically insulating (polymer) material.

Although not shown in the drawings, an electrode arrangement can be accommodated or integrated in the gun barrel 3 of the spray gun 1 in order, if necessary, to electrostatically charge the coating material to be sprayed. For this purpose, in particular the gun barrel 3 inside corresponding voltage multiplier unit, which is connected to the electrode arrangement. The voltage multiplier unit and the electrode assembly cooperate to create an electric field for electrostatically charging the material to be sprayed onto an object

To produce coating material.

The coating material to be sprayed, in particular coating powder carried along in an air stream, is fed to the spray gun 1 from a powder source not shown in the drawings. The flow of coating powder carried in air is controlled by a

Coating material supply line through an adapter 7 provided on the lower area of the handle part 2 into an adapter 7 running through the handle part 2

Coating material line fed.

In addition, connections 9a for compressed air and connections 9b for electrical energy are provided at the lower end region of the handle part 2.

The back of the main body of the spray gun 1 is in the

Embodiment of the spray gun 1 according to the invention shown in the drawings covered over a rear shell 10.

It is provided here that the rear shell 10 can be detachably and interchangeably attached to the rear of the base body of the spray gun 1, with the rear shell 10 preferably being fixed to the base body 4 of the spray gun 1 by a single screw 30 guided through the rear shell 10 in the attached state.

A further screw 31 can optionally be provided which, through the lower end region of the base body of the gun barrel 3, cooperates in a suitable manner with a screw receptacle provided in the interior of the rear shell 10.

The rear shell 10 essentially has a first area designed as a grip shell 11 and a second area designed as a cover shell 12, the first area designed as a grip shell 11 serving in particular to cover the base 4 of the gun barrel 3 of the spray gun 1 on the rear. The second area formed as a cover shell 12 of The rear shell 10 serves to cover the rear of a rear area of the gun barrel 3.

A connecting element 14 in the form of a hook-shaped area is also provided on the second area of the rear shell 10. About this

Connecting element 14, the spray gun 1 in its fully assembled state can be detachably connected, for example, to a holder.

According to the invention, it is particularly provided that the entire rear shell 10 together with the at least one connecting element 14 (hook-shaped area) is designed as a monolithic plastic component, in particular a plastic injection-molded part.

As indicated in the drawings, the rear shell 10 can also have a

Have transition area 13, which connects the first area designed as a grip shell 11 with the second area designed as a cover shell 12. This transition area 13 is also (as part of the entire rear shell 10) monolithically and integrally connected to the handle shell 11 and the cover shell 12.

The first area, designed as a grip shell 11, is approximately U or V-shaped in cross section, at least in some areas, and has a rear wall and two side walls formed integrally thereon. In this case, it is provided in particular that the outer surfaces of the rear wall and the side walls of the first area formed as a grip shell 11 formed thereon have a configuration adapted to increase the grip security.

In particular, the one shown in the drawings is exemplary

Embodiment for increasing the grip security, a polygonal wave shape that is adapted to the hand of the operator of the spray gun 1, and specifically adapted in an ergonomic manner, is provided.

The illustration in FIG. 3 it can be seen in particular that, in the embodiment shown in the drawings, in the rear wall of the first area of the rear shell 10, which is designed as a handle shell 11

Cable strain relief 15 is integrated. With regard to the second region of the rear shell 10, which is designed as a cover shell 12, it is provided that this is at least in cross section

is approximately U-shaped in some areas with a rear wall and two side walls integrally formed thereon. In addition, the second area designed as a cover shell 12 has a first area designed as a grip shell 11 at least partially or in areas

opposite upper wall, which is integrally formed on the rear wall and the side walls formed thereon of the second area formed as a cover shell 12. On this upper wall, the connecting element 14 is formed in one piece in the form of a hook-shaped element.

The isometric view, for example according to FIG. 3 it can be seen that in the exemplary embodiment in the rear wall of the second area, which is designed as a cover shell 12, there is an in particular recessed opening 16 for an operating element 5 of the spray gun 1

is trained. In particular, this opening 16 is formed that

Control element 5 of the spray gun 1 to be received and embedded in a recessed manner.

Furthermore, it can be seen from the drawings that in the rear shell 10 and preferably in the material of a side wall of the second area formed as a cover shell 12, at least one electrically conductive area

Earthing element 17 is integrated. The at least one grounding element 17 serves to ground a counter electrode of the spray gun or to connect to it

To set ground potential. For this purpose, in the assembled state of the spray gun 1, the grounding element 17 integrated in the rear shell 10 can be connected via a grounding conductor, such as a galvanically conductive one

Connecting web, with one in the vicinity of a charging electrode

Spray gun arranged counter electrode can be connected to the

To connect the counter electrode to an electrical potential which is different from the electrical potential to which the charging electrode

connected. In this way, at least some of the free ions generated when the coating powder is electrically charged can be used via the counter electrode and the grounding element 17 integrated in the rear shell

be included. Preferably, the grounding element 17 integrated in the rear shell is electrically conductively connected to the grounding or a potential connection via an electrical line running in particular in the interior of the handle 2 of the spray gun 1.

On the front longitudinal edge of the side walls of the rear shell 10, a centering 18 in the form of a centering tab is provided at least in some areas, via which an in particular automatic alignment of the position of the rear shell 10 relative to the rear of the base body of the spray gun 1 when the rear shell 10 is mounted on the rear the base body is made possible.

In addition, in the embodiment shown in the drawings, at least one guide element 21 formed in the interior of the rear shell 10 is provided in order to simplify a plug-in movement when the rear shell 10 is mounted on the rear of the base body of the spray gun 1.

The end faces 19 of the front longitudinal edge of the side walls of the rear shell 10 are preferably designed to be stepped in order to be able to form a type of labyrinth seal with a corresponding area on the rear side of the base body of the spray gun 1.

The invention is not limited to the exemplary embodiment shown schematically in the drawings, but results from an overview of all the features disclosed herein.

Claims

MEISSNER BOLTE

P.O. Box 102605

86016 Augsburg

February 27, 2020

Gema Switzerland GmbH A / GEMA-159-PC

TR / Ij

REAR SHELL FOR A SPRAY GUN AND SPRAY GUN WITH A

SUCH REAR SHELL

Claims

1. Rear shell (10) for a spray gun (1), in particular a powder spray gun

(1), the spray gun (1) having a handle part (2) and one with the handle part

(2) connected gun barrel (3), and wherein the rear shell (10) can be detachably and interchangeably attached to the rear of a base body (4) of the spray gun (1) and has a first area designed as a handle shell (11) and for the rear cover of a rear area of the gun barrel (3) has a second area designed as a cover shell (12), with at least one connecting element (14) being provided on the second area of the rear shell (10) for the formation of a detachable connection with an at least regionally

Complementary to this, the entire rear shell (10), together with the at least one connecting element (14), is designed as a monolithic plastic component, in particular a plastic injection-molded part.

2. rear shell (10) according to claim 1,

wherein the rear shell (10) has a transition area (13) which connects the first area designed as a handle shell (11) to the second area designed as a cover shell (12). 2

3. rear shell (10) according to claim 1 or 2,

wherein the first area, designed as a grip shell (11), is approximately U- or V-shaped in cross section, at least in some areas, with a rear wall and two integrally formed thereon

Sidewalls.

4. rear shell (10) according to claim 3,

the outer surfaces of the rear wall and the one thereon

molded-on side walls of the first area designed as a grip shell (11) has a configuration adapted to increase grip security, in particular a surface configuration, and in particular has a polygonal wave shape adapted to the human hand.

5. rear shell (10) according to claim 3 or 4,

wherein at least one cable strain relief (15) is preferably integrated in the rear wall of the first area, which is designed as a grip shell (11).

6. rear shell (10) according to one of claims 1 to 5,

wherein the second area, designed as a cover shell (12), is approximately U-shaped in cross section, at least in some areas, with a rear wall and two side walls integrally formed thereon.

7. rear shell (10) according to claim 6,

wherein the second area designed as a cover shell (12) furthermore has an upper wall at least partially or partially opposite the first area designed as a handle shell (11), which is integral with the rear wall and the side walls formed thereon of the second, designed as a cover shell (12) Area is formed.

8. rear shell (10) according to claim 7,

wherein the at least one connecting element (14) is formed in one piece on the upper wall and is preferably designed as a hook or eye-shaped element. 3

9. rear shell (10) according to one of claims 6 to 8,

wherein in the rear wall of the second area designed as a cover shell (12) at least one, in particular, set-back opening (16) for at least one operating element and / or display element (5)

Spray gun (1) is provided, the at least one opening (16) being formed, the at least one operating element and / or

Display element (5) in particular to receive and / or embed in a recessed manner.

10. rear shell (10) according to one of claims 6 to 9,

wherein in the rear shell (10) and preferably in a side wall of the second area formed as a cover shell (12) at least one

A receptacle for a switch and preferably an element which is integrally formed so that it can move relative to the rear shell (10) is designed for actuating a switch.

11. rear shell (10) according to one of claims 6 to 10,

wherein at least one galvanically conductive grounding element (17) is integrated in the rear shell (10) and preferably in the material of a side wall of the second area designed as a cover shell (12).

12. rear shell (10) according to one of claims 1 to 11,

wherein a centering (18), in particular in the form of at least one centering tab or the like, is provided on the front longitudinal edge of the side walls of the rear shell (10) at least in some areas, in particular for the independent alignment of the position of the rear shell (10) relative to the rear of the base body (4 ) the spray gun (1) when assembling the rear shell (10) on the back of the base body (4).

13. rear shell (10) according to one of claims 1 to 12,

wherein on the front longitudinal edge of the side walls of the rear shell (10), and in particular on the end face of the front longitudinal edge of the

Side walls of the rear shell (10) a stepped area (19) is provided at least in some areas, the end faces in particular

are designed complementary to a corresponding area on the rear side of the base body (4) of the spray gun (1). 4th

14. rear shell (10) according to one of claims 1 to 13,

wherein at least one and preferably exactly one opening (20) for receiving a screw (30) is formed in the rear shell (10) for releasably fixing the rear shell (10) to the base body (4) of the spray gun (1).

15. rear shell (10) according to one of claims 1 to 14,

wherein the entire rear shell (10) together with the at least one connecting element (14) as a monolithic component from a

antistatic plastic material, in particular polyamide-12, is formed.

16. Spray gun (1), in particular powder spray gun (1), which has a handle part (2) and a gun barrel (3) connected to the handle part (2), a rear shell (10) according to one of claims 1 to 15 the back of a base body (4) of the spray gun (1) is attached.