# Patent

## Title
Fluid reservoir for a paint spray gun

## Abstract

The invention relates to a fluid reservoir for a paint spray gun with a container (1) and a cover (2) that is attachable on this container and has a connection part (3) to enable attaching the fluid reservoir on the paint spray gun or on an adapter, wherein the container (1) has a ventilation opening (6) that can be closed by a valve (5). In a fluid reservoir known from the state of the art, the valve is constructed in the form of a sliding valve. Here, there is the risk that the ventilation opening is not completely closed if the slide of the sliding valve has not been pushed completely into the valve housing. In order to provide a fluid reservoir with a valve that can be easily actuated manually and that can be closed reliably, it is provided for the fluid reservoir according to the invention that the valve (5) has a closing element (8) that can pivot like a rocker about a pivot axis (7) for closing the ventilation opening (6) in a fluid-tight way.

## Background
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority under 35 U.S.C. §119 to German Patent Application No. 10 2006 057 621.7 filed Dec. 5, 2006, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a fluid reservoir for a paint spray gun.
BACKGROUND OF THE INVENTION
Such a fluid reservoir is known from the state of the art, for example, from WO 98/32539. This fluid reservoir is provided for one-time use and comprises a container made from plastic and a cover that can be set on top for closing this container. On the top side of the cover there are connection means for the placement and attachment of the fluid reservoir on a paint spray gun or an adapter attached to this gun. In this way, the fluid reservoir is set “upside-down” on the paint spray gun, that is, with the cover side pointing downward. The paint located in the fluid reservoir then flows downward into the paint inlet channel of the paint spray gun due to the force of gravity. Pressure equalization between the interior of the paint reservoir and the surroundings is necessary to allow the gravity-driven flow of paint. To guarantee this pressure equalization, a ventilation opening, which can be closed by means of an adhesive strip or a manually actuated valve, is formed in the container base.
Another fluid reservoir of this generic type is known from DE 10 2004 021 298 A1. For this fluid reservoir, the valve is constructed as a sliding valve for closing the ventilation opening. For such a sliding valve, there is the risk that the ventilation opening is not completely closed if the slider has not been completely pushed into the valve housing. In this case, there is the risk when filling the fluid reservoir with paint that paint will run out through the ventilation opening incompletely closed with the slide.
Starting with this state of the art, the invention is based on the task of presenting a fluid reservoir with a valve, easily actuated manually, for the reliable closing of the ventilation opening.
SUMMARY OF THE INVENTION
This task is achieved with a fluid reservoir as set forth in the claims. Advantageous embodiments of this fluid reservoir are to be taken from the dependent claims.



BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in more detail below using an embodiment with reference to the enclosed drawings. The drawings show:
FIG. 1, a fluid reservoir according to the invention in section;
FIG. 2, detail view of the valve of the fluid reservoir of FIG. 1 in the closed valve position (FIG. 2a) and the open valve position (FIG. 2b);
FIG. 3, perspective detail views of the valve of the fluid reservoir of FIG. 1, in exploded representations viewed obliquely from above (FIG. 3a) or obliquely from below (FIG. 3b).



DETAILED DESCRIPTION OF THE INVENTION
The fluid reservoir shown in FIG. 1 comprises a cup-shaped container 1 and a cover 2 that can be screwed onto this container by means of a thread. The cover 2 has an outlet port with an outlet opening on its top side. On the outside of the outlet port there is a connection part 3, which is used for the placement and attachment of the fluid reservoir on a paint spray gun or on an adapter arranged between the paint spray gun and the fluid reservoir. In the embodiment shown in FIG. 1, the connection part 3 comprises a thread and a wedge-shaped groove, which interact with corresponding connection parts on the paint spray gun, namely a corresponding internal thread and a pin for engaging in the groove. Both the container 1 and also the cover 2 are preferably constructed as injection-molded parts made from plastic.
For filling the container 1, the cover 2 is removed and then replaced after filling. Then the cover 2 is set and attached with its connection part 3 on the connection part of a paint spray gun or an adapter. During the spraying process, the fluid reservoir is located on the top side of the paint spray gun and the liquid in the container runs into the paint inlet channel of the paint spray gun due to the force of gravity.
To maintain the gravity-driven flow of the fluid, pressure equalization between the interior of the container 1 and the surroundings is necessary. For this reason, a ventilation opening 6 is provided in a wall 9 of the container 1. In the embodiment shown in the figures, the ventilation opening 6 is in the container base 4. Alternatively, however, the ventilation opening 6 can also be formed in the side wall of the container preferably in the vicinity of the base 4. For closing the ventilation opening 6, a valve 5 is provided that is arranged on the bottom side of the container base 4. In addition, a surrounding cylindrical rim 21 is formed on the outer periphery on the bottom side of the container base 4. This rim projects beyond the valve 5, in order to be able to set down the container 1 on the base 4 for filling.
The valve 5 is constructed as a rocking valve that has a closing element 8 that can pivot about a pivot axis 7 for closing the ventilation opening 6. The valve 5 is shown in detail views in FIGS. 2 and 3 wherein FIG. 2a shows the valve 5 in the closed valve position and FIG. 2b shows it in the open valve position, and FIGS. 3a and 3b shows the components of valve 5 in the form of exploded views.
As can be seen from FIGS. 2 and 3, the valve 5 comprises a closing element 8, which can pivot about a pivot axis 7 like a rocker. The closing element 8 can pivot between a first valve position in which the closing element 8 closes the ventilation opening 6 (as shown in FIG. 2a), and a second valve position in which pressure equalization is allowed between the interior of the container 1 and the surroundings (as shown in FIG. 2b). In the first valve position, in which the closing element 8 closes the ventilation opening 6, the closing element 8 is preferably fixed in the ventilation opening 6 by means of a manually releasable gripping or latching mechanism.
The closing element 8 is composed of a first arm 12 and a second arm 13 and a pivot bearing 14 formed integrally on the bottom side of the closing element 8. The pivot bearing 14 has an essentially cylindrical shape and is clipped into a receiver bearing 15 integrally formed on the base 4 of the container 1. The receiving bearing 15 is shaped so that the pivot bearing 14 can be detachably clipped or latched in the bearing. Alternatively, the closing element 8 can also be non-detachably attached, and thus captive, so that it can pivot on the receiver bearing 15 by means of the pivot bearing 14.
A plug 10 with a cylindrical form or tapering conically forward and arranged integrally on a plug plate 11 is constructed on the top side of the first arm 12 of the closing element 8. In the closed valve position (FIG. 2a) the plug 10 engages in the ventilation opening 6 and closes this in a fluid-tight way. Here, the plug plate 11, which is greater in diameter relative to the plug 10, rests on the outside wall 9 of container 1 in which the ventilation opening 6 is formed. A circular groove 22 is formed in the plug plate 11, which preferably has a cylindrical construction just like the plug 10. In the closed valve position (FIG. 2a), a ring 16 formed around the ventilation opening 6 on the bottom side of the wall 9 and projecting from the wall 9 engages tightly in this groove 22. Through this gripping arrangement of the ring 16 in the groove 22 on the plug plate 11, a releasable fixing of the closing element 8 in the closed valve position and simultaneously a liquid-tight engagement of the plug 10 in the ventilation opening 6 is guaranteed. Preferably, the diameter of the plug 10 is matched to the diameter of the preferably circular ventilation opening 6, so that the plug 10 engages tightly in the ventilation opening 6, so that in this way a releasable fixing of the closing element 8 in the ventilation opening 6 for a closed valve position is also enabled. For this purpose, the diameter of the plug 10 is preferably tapered conically in the front.
In an alternative embodiment, the groove 22 is wider in the plug plate 11 than the width of the ring 16. A gripping effect is then realized when the closing element 8 is brought into the closed valve position. In this embodiment, the groove 22 in the plug plate 11 is used for retaining fluid that during the spraying process, has possibly settled in the region around the ventilation opening 6 and especially on the ring 16. In this embodiment, a peripheral surrounding collar 20, which surrounds the ring 16 in the closed valve position (FIG. 2a), is formed on the plug plate 11. The collar 20 acts as spatter protection when the ventilation opening 6 is closed by the closing element 8 and prevents the spattering of fluid or paint residue that has settled around the ventilation opening 6, and especially in the region of the ring 16, during the spraying process.
The valve 5 can be brought manually into the open valve position (FIG. 2b) from the closed valve position (FIG. 2a) through pressure on the second arm 13. With manual pressure on the second arm 13 of the closing element 8, the pivot bearing 14 pivots in the receiver bearing 15 by an angle of ca. 10 to 45°. To prevent excessive pivoting of the closing element 8, a stop is provided that in the embodiment shown in the figures is formed by an inclined surface 17 on the bottom side of the receiver bearing 15. The closing element 8 can be pivoted only so far by pressure on the second arm 13 until the top side of the second arm 13 contacts the inclined surface 17, as shown in FIG. 2b. For closing the ventilation opening, the closing element 8 can be brought into the closing position (FIG. 2a) through manual pressure on the first arm 12.
To be able to fix the closing element 8 both in the closed and also in the open valve position, catch elements 18, 19 corresponding to each other are preferably arranged on the pivot bearing 14 and on the receiver bearing 15. In the embodiment that can be taken from the drawings of FIGS. 3a and 3b, the catch elements 18, 19 are constructed in the form of recesses 18 in the pivot bearing 14 and catch tabs 19 corresponding to the recesses 18 on the receiver bearing 15. To be able to lock the closing element 8 both in the closed valve position and also in the open valve position on the receiver bearing 19, there are two recesses 18 in the pivot bearing 14 that lie on the outside of the semi-cylindrical pivot bearing 14 at opposing positions, and two corresponding catch tabs 19 on the receiver bearing 15.
In a preferred embodiment not shown here, a sealing ring is provided, which can be arranged either on the plug 10 or on the plug plate 11 or also in the ring 16, to guarantee the best possible fluid-tight closing of the ventilation opening 6.

## Claims

1. A fluid reservoir for a paint spray gun comprising:
a cup-shaped container, the cup-shaped container comprising:
a substantially open end;
a substantially closed end opposite the open end, the substantially closed end defining a base of the container;
a sidewall joining the open and closed ends;
a cover sized and dimensioned to releaseably close the substantially open end;
a ventilation opening in the base or in the sidewall, the ventilation opening encircled by a ring formed by projections of the base or of the sidewall; and
a valve assembly positioned on the closed end and cooperative with the ventilation opening to releaseably close the ventilation opening, the valve assembly comprising:
a bearing block having a cylindrical recess forming a receiver bearing; and
a rocking arm, the rocking arm comprising:
a pivot bearing having a cylindrical portion and an extension portion, the extension portion integrally formed with or attached to the rocking arm, having a length that extends from a first end of the cylindrical portion to a second end of the cylindrical portion, and a trapezoidal cross section, wherein the cylindrical portion of the pivot bearing is pivot-mounted to the receiver bearing for pivoting the rocking arm between a closed position and an open position, wherein the ventilation opening is open in the open position and closed in the closed position;
a first arm portion having a valve plug sized and dimensioned for releaseably closing the ventilation opening arranged on a plug plate, the plug plate having a cylindrical or a frustoconical form and a diameter greater than a diameter of the valve plug; and
a second arm portion opposite the first arm portion, the second arm portion pressable for releasing the valve plug from closing the ventilation opening,
wherein the ring of the ventilation opening engages in a circular groove formed in the plug plate when the rocking arm is in the closed position.

2. The fluid reservoir for a paint spray gun according to claim 1, wherein the ring of the ventilation opening is configured for blocking fluid splatter occurring when the valve assembly is pivoted to close the ventilation opening.

3. The fluid reservoir for a paint spray gun according to claim 1, wherein the circular groove formed in the plug plate has a width greater than a width of the ring encircling the ventilation opening.

4. A paint cup for a paint spray gun comprising:
a cup-shaped container, the container comprising:
a substantially open end having a threaded connector portion around a periphery thereof, the substantially open end defining a top end of the container;
a substantially closed end opposite the open end, the substantially closed end defining a bottom end of the container;
an air vent formed through the bottom end of the container;
a ring formed around the air vent projecting from the bottom end of the container;
a sidewall joining the open and closed ends;
a cover sized and dimensioned to releaseably close the substantially open end; and
a valve assembly positioned on the closed end and cooperative with the air vent to releaseably close the air vent, the valve assembly comprising:
a bearing block having a cylindrical recess forming a receiver bearing having a catch tab;
a rocking arm having a first arm portion, a second arm portion extending in a direction opposite to the first arm portion, and a pivot bearing pivot-mounted to the receiver bearing of the bearing block for pivoting the rocking arm between a first position and a second position, the pivot bearing having a cylindrical portion and an extension portion, the extension portion integrally formed with or attached to the rocking arm, having a length that extends from a first end of the cylindrical portion to a second end of the cylindrical portion, and a trapezoidal cross section, wherein the air vent is closed in the first position and open in the second position;
a plug plate formed on the first arm portion of the rocking arm; and
a cylindrical or frustoconical valve plug formed on the plug plate having a smaller diameter than a diameter of the plug plate, the valve plug sized and dimensioned for releaseably closing the air vent fluid-tight;
wherein the rocking arm pivots on the cylindrical portion of the pivot bearing at a point between the first and the second arm portions, the second arm is pressable to rotate the pivot bearing in the receiver bearing from a first position in which the air vent is closed to a second position in which the air vent is open, and wherein the ring engages in a circular groove formed in the plug plate when the pivot bearing is pivoted from the second position into the first position.

5. The paint cup for a paint spray gun according to claim 4, wherein the circular groove formed in the plug plate has a width greater than a width of the ring formed around the air vent.

6. The paint cup for a paint spray gun according to claim 4, wherein the air vent and the valve assembly are positioned proximate a periphery of the closed end of the container.

7. The paint cup for a paint spray gun according to claim 4, further comprising a stop arranged for limiting movement of the pivot bearing substantially beyond the second position.

8. The paint cup for a paint spray gun according to claim 7, wherein the stop is an inclined surface on the bearing block.

9. The paint cup for a paint spray gun according to claim 4, wherein the cylindrical portion of the pivot bearing is mateably and pivotably-connectable to the cylindrical recess of the bearing block.

10. The paint cup for a paint spray gun according to claim 4, wherein the first and the second arm portions of the rocking arm extend to each side of the pivot bearing.

11. A paint container for a paint spray gun comprising:
a substantially open end having a connector portion around a periphery thereof;
a substantially closed end opposite the open end;
an air vent formed through the closed end;
a ring surrounding the air vent projecting from the closed end;
a cylindrical sidewall joining the open and closed ends;
a rim surrounding and extending beyond the closed end in a direction away from the open end; the rim configured to support the paint container in a filling and storage position in which the open end is positioned topmost with respect to the closed end;
a cover sized and dimensioned to releaseably close the substantially open end, the cover including:
a. a connector portion mateable with the connector of the open end to form a liquid tight seal, and
b. a dispensing port having a connector portion for affixing the cover and attached container onto the paint spray gun;
a valve assembly positioned on the closed end and cooperative with the air vent to releaseably close the air vent, the valve assembly including:
a. a bearing block integrally formed from material of the closed end, the bearing block having a cylindrical recess forming a receiver bearing, a first catch element, and a second catch element; and
b. a rocking arm pivotally connected to the bearing block, the rocking arm including:
i. a first arm portion having a valve plug dimensioned for releaseably closing the air vent arranged on a plug plate, the plug plate having a cylindrical or a frustoconical form, a circular groove formed therein, and a diameter greater than a diameter of the valve plug;
ii. a second arm portion extending opposite the first arm portion, the second arm portion pressable for releasing the valve plug from closing the air vent; and
iii. a pivot bearing having a cylindrical portion and an extension portion, the extension portion integrally formed with or attached to the rocking arm, having a length that extends from a first end of the cylindrical portion to a second end of the cylindrical portion, and a trapezoidal cross section, wherein the cylindrical portion of the pivot bearing is pivot-mounted to the receiver bearing of the bearing block for pivoting between a first position in which the air vent is closed and a second position in which the air vent is open;

wherein the ring surrounding the air vent engages the circular groove in the plug plate when the pivot bearing is in the first position.

12. The paint container for a paint spray gun according to claim 11, wherein the pivot bearing comprises:
a third catch element mateable with the first catch element of the bearing block, the mating first and third catch elements configured to releaseably maintain the valve assembly in the first position when the air vent is closed; and
a fourth catch element mateable with the second catch element of the bearing block; the mating second and fourth catch elements configured to releaseably maintain the valve assembly in the second position when the air vent is open,
whereby the valve assembly is prevented from moving from the first position to the second position when the first and third catch elements are mated and the valve assembly is prevented from moving from the second position to the first position when the second and fourth catch elements are mated.

13. The paint cup for a paint spray gun according to claim 11, wherein the circular groove formed in the plug plate has a width greater than a width of the ring surrounding the air vent.

14. The paint container for a paint spray gun according to claim 11, wherein the valve plug has a conical, tapered form sized and dimensioned for inserting into and sealing the air vent.

15. The paint container for a paint spray gun according to claim 11, wherein the pivot bearing of the rocking arm is snap connected to the receiver bearing of the bearing block.

16. The paint container for a paint spray gun according to claim 12, wherein the third and fourth catch elements are formed as recesses in the pivot bearing.