Filling device for filling an aerosol container with a liquid

Abstract

Filling device for filling an aerosol container with a liquid, such as paint, which device comprises a cup for the liquid for the aerosol container, which cup is provided with an injection opening at its bottom surface; a pusher element for pushing the liquid from the cup via the injection opening to the aerosol container; and a piston head that is adapted to be detachably fixed on the end of the pusher element to be in contact with the liquid in the cup when the liquid is transferred from the cup to the aerosol container, which piston head is in the form of a scrap-er in continuous contact with the side wall of the cup during the liquid transferring operation, wherein the detachable fixing of the piston head allows the piston head to be withdrawn together with the pusher element from the cup after the liquid transferring operation is done.

Claims

1. A filling device for filling an aerosol container with a liquid, such as paint, the filling device comprising: a cup for the liquid for the aerosol container, which cup is provided with an injection opening at its bottom surface, a pusher element for pushing the liquid from the cup via the injection opening to the aerosol container, a piston head that is adapted to be detachably fixed on the end of the pusher element to be in contact with the liquid in the cup when the liquid is transferred from the cup to the aerosol container, which piston head is in the form of a scraper in continuous contact with the side wall of the cup during the liquid transferring operation, wherein the detachable fixing of the piston head allows the piston head to be withdrawn together with the pusher element from the cup after the liquid transferring operation is done, and a support element with a counter surface for the piston head, wherein the pusher element can be raised such that the piston head contacts the counter surface of the support element to cause detachment of the piston head from the end of the pusher element.

2. The filling device according to claim 1, wherein the detachable fixing of the piston head to the pusher element is implemented with interlocking forms.

3. The filling device according to claim 1, wherein the filling device comprises devices for detecting the attachment of the piston head to the pusher element.

4. The filling device according to claim 1, wherein the filling device comprises a door construction for inserting the aerosol container into the filling device and removing the aerosol container from the filling device, which door construction comprises support for the aerosol container.

5. The filling device according to claim 4, wherein the door construction comprises support for the cup for the liquid or for a part supporting the cup.

6. The filling device according to claim 4, wherein the support for the aerosol container in the door construction supports the aerosol container from a lower end area of the container, and that the support for the aerosol container comprises a mechanism for adjusting the vertical position of the support surface.

7. The filling device according to claim 4, wherein the door construction is formed as a detachable entity from the rest of the filling device, to which entity the aerosol container and the cup for the liquid is attachable prior to inserting the door construction into the filling device.

8. The filling device according to claim 4, wherein the support for the aerosol container in the door construction comprises at least one magnet.

Description

(1) Exemplifying embodiment of the invention and its advantages are explained in greater detail below in the sense of example and with reference to accompanying drawings, where FIG. 1 shows schematically an embodiment of a filling machine of the invention as a sectional view, and FIGS. 2A-2C show schematically an embodiment for a door construction for the filling device of FIG. 1.

(2) FIG. 1 shows schematically as a sectional view a filling device 1 for filling an aerosol container 2 with a liquid. The filling device 1 comprises a frame 3 defining the outer boundary of the device and providing suitable support and fixing surfaces for the other parts of the device, as well as cover and protection for the user during the filling process.

(3) The frame 3 comprises a support section 6 dividing the inside area restricted with the frame into upper and lower portions. The enclosed upper portion of the frame 3 comprises a pusher element 4, which is typically an axially symmetrical piece in form of a cylinder, and a device 5 for moving the pusher element in the directions shown with a double head arrow in the figure. The pusher element 4 extends from the upper portion of the frame 3 through the support section 6 into the lower portion of the frame. The device 5 for moving the pusher element 4 can be any device suitable for providing linear back-and-forth movement, such as hydraulic or pneumatic drive, but preferably it is an electric motor with a mechanism for converting rotational movement to a linear movement. The enclosed upper part of the frame 3 also includes the required electronics and logic circuits (not shown) for operating the filling device 1. Alternatively, the filling device 1 can be manually operated, where the linear back-and-forth movement of the pusher element 4 is achieved with a mechanism comprising a lever extending outside of the frame 3, for example, wherein by manually moving the lever the pusher element is moved inside the filling device during the filling operation of the aerosol container 2.

(4) The lower portion of frame 3 is located below the support section 6 and is equipped with a suitable closeable opening for allowing access inside the lower portion. Inside the lower portion of frame 3, fixed on the end of the pusher element 4, is a piston head 7. In this embodiment the detachable fixing of the piston head 7 to the pusher element 4 is implemented via edge protrusions formed in the piston head, which edge protrusions are set in a counter groove formed on the side surface of the pusher element, thus achieving a fixing via interlocking forms.

(5) Inside the lower portion of frame 3 is also located a cup 8 for a liquid, such as paint, which cup is located inside of a support piece 9. The cup 8 and the support piece 9 are in this embodiment in form of hollow cylindrical pieces having open upper surfaces and bottom surfaces. When cup 8 is set in the support piece 9, the outer side surfaces of the cup set against the inner side surfaces of the support piece and the outer bottom surface of the cup sets against the bottom inner surface of the support piece. In the center area of the bottom on the cup 8 there is formed an injection opening with protrusion extending outwards from the bottom surface of the cup, through which hole the liquid in the cup is pressed inside the aerosol container 2. Corresponding opening is also formed in the bottom of the support piece 9.

(6) The frame 3 of the filling device 1 is preferably also equipped with supports 17, which support the bottom surface of the support piece 9. With these supports 17 the force created by the downwards movement of the piston 4 is conveyed to the frame 3 of the filling device 1 and not to the structure of the aerosol container 2. The aerosol container 2 is supported via its lower portion so that it remains in contact with the cup 8 and the support piece 9 during the transferring of the liquid from the cup to the aerosol container.

(7) At the bottom outer surface of the support piece 9 there is suitable means for connecting the support piece to the aerosol container 2 in such a way that the protrusion with the injection opening in the bottom of the cup 8 comes into contact with the valve of the aerosol container.

(8) When the filling device 1 is used, the cup 8 is set in the support piece 9, the support piece is connected to the upper end of the aerosol container 2 at the area of the valve of the aerosol container, and the liquid to be transferred into the aerosol container is measured and added in the cup. These actions can be done in any suitable order.

(9) Then the entity comprising the aerosol container 2, support piece 9, cup 8 and the liquid is placed and supported inside the lower portion of the frame 3. After this placement the opening through which the mentioned entity is placed inside the filling device 1 is closed and the transferring process can be started by activating the device 5 for moving the pusher element 4 downwards and thus pushing the liquid from the cup 8 inside the aerosol container 2 via the injection opening. The downwards movement of the pusher element 4 is continued until the outer surface of the piston head 7 is substantially in contact with the bottom inner surface of the cup 8 thus making sure that substantially all of the liquid is transferred from the cup to the aerosol container 2.

(10) The piston head 7 is formed and dimensioned such, that the side edge of the piston head sets itself tightly against the inner side surface of the cup 8 thus scraping substantially all the liquid with it from the side surface of the cup. This also helps to maintain the required pressure in the liquid for injecting it through the injection opening of the cup 8 and inside the aerosol container 2.

(11) Once the transfer operation is done, the pusher element 4 together with the piston head 7 is withdrawn from inside the cup 8 with the device 5, the opening allowing access to the lower portion of frame 3 is opened, and the entity comprising the aerosol can 2, the support piece 9 and the cup 8 is removed from the filling device 1. After the support piece 9 together with the cup 8 is detached from the filled aerosol container 2, the filled aerosol container is ready for packaging.

(12) If a new aerosol container is filled with the same liquid, the above described process is repeated by only attaching a new aerosol container 2 to the support piece 9 and adding a new amount of liquid in cup 8.

(13) If a different liquid, such as different color of paint for example, the piston head 7 and the cup 8 needs to be changed before starting the new filling process with a new aerosol container 2, so that contamination of the new liquid can be avoided. The changing of the piston head 7 is advantageously done in a following way in this embodiment. After the end of the last filling process the raising of the pusher element 4 is continued until the upper edge of the piston head 7 sets against the lower surface of the support section 6, and then the pusher element is raised more so that the lower surface of the support section forces the piston head 7 to deform and detach from the pusher element. For this detachment process of the piston head 7, a separate vessel for the detached piston head 7 is preferably inserted at the place of the filled aerosol container 2 after its removal together with the cup 8 and the support piece 9 from the filling device 1, to which vessel the detached piston head 7 drops after it is detached from the pusher element 4. Before a new filling process is started a new piston head 7 is attached to the pusher element.

(14) Because the use of the filling device 1 without the piston head 7 in its place on the pusher element 4 would lead to significant cleaning operation of the filling device, the filling device advantageously comprises a suitable means (not shown in figures) for detecting that the piston head 7 is attached to the pusher element 4. These detecting means also advantageously comprise or are connected to means for preventing the activation of the filling device 1 without the piston head 7 at its place. These sensing means can be implemented with a suitable prior art sensing device attached to any rigid section of the filling device 1, that detects the presence of the attached piston head, such as a microswitch for example.

(15) FIGS. 2A-2C show schematically an embodiment of a door construction 10 for the filling device 1 of FIG. 1. FIG. 2A shows the door construction 10 with the aerosol container 2 and support piece 9 as a perspective view, FIG. 2B shows a cross-sectional view of FIG. 2A, and FIG. 2C shows an enlargement of the area B of FIG. 2B.

(16) The door construction 10 shown in FIGS. 2A-2C comprises a door plate 13, a lower support portion 11 and upper support 12. The lower support portion 11 extends from the lower end area of the inner side surface of the door plate 13, and the upper support 12 extends from the upper end area of the inner side surface of the door plate.

(17) When the door construction 10 is placed at its place in the filling machine 1, the door plate 13 covers whole of the area of the closable opening formed in the lower portion of the frame 3 of the filling device 1. The outer side surface of the door construction 10 also preferably forms one side wall of the lower portion of the filling device 1, whereby the filling device has preferably square cross-section perpendicularly in relation to its vertical longitudinal axis. Further, the door construction is preferably an entity that can be completely removed from the rest of the filling device 1, so that inserting and removing of the aerosol canister 2, cup 8 and support piece 9, and the filling of the cup 8 with the liquid, may be done without hindrance from the rest of the structure of the filling machine 1.

(18) The lower support portion 11 of the door construction 10 is formed to support the bottom of the aerosol container 2 to be filled, and the upper support 12 is formed to support the upper side surface and top surface of the support piece 9.

(19) Since the outer dimensions of the aerosol containers 2 to be filled with the filling device 1 can vary, the lower support portion 11 is formed of two parts 11a and 11b, wherein the vertical distance of the upper part 11b from the lower part 11a is adjustable accordingly. This adjustability is achieved with a spring-loaded connection between the parts 11a and 11b. The spring-loaded connection between the lower part 11a and the upper part 11b is formed in this embodiment with four springs 14, which are arranged between the parts 11a and 11b, and with two horizontally extending screws 15. The screws 15 are screwed in vertically extending threaded holes in the lower part 11 a so that their end portion set in openings 16 formed in the upper part 11b. The openings 16 are dimensioned so, that their vertical dimension defines the maximum vertical adjustability between the lower part 11a and the upper part 11b. In an unloaded situation the lower inner surfaces of the openings 16 set against the ends of the screws 15 to keep the parts 11a and 11b sufficiently supportingly fixed to each other.

(20) When the aerosol container 2 together with the support piece 9 fixed at its upper end is inserted to the door construction 10, the upper part 11b of the lower support portion 11 is pressed downwards so that the bottom of the aerosol container 2 can be set on a depression formed in upper surface of the upper part 11b and simultaneously the upper side surface and top surface of the support piece 9 are set against the corresponding support surfaces of the upper support 12 of the door construction 10. Once the aerosol container 2 together with the support piece 9 are properly positioned, the upper part 11b is released and the spring force from the springs 14 keeps the aerosol container and the support piece at their place in relation to the door construction 10. Now the door construction 10 together with the aerosol container 2 and the support piece 9 form an entity that can be handled together, which helps the insertion of the aerosol container and the support piece together with the cup 8 filled with the liquid into the filling device 1. This insertion is preferably done by purely horizontal movement of this entity in relation to the rest of the filling machine 1.

(21) The upper support 12 of the door construction is formed so, that the support surfaces define proper positioning of the support piece 9 in relation to the upper support, and so that the upper support 12 allows for insertion of the cup 8 with the liquid in the support piece 9 when it is set at its place in the door construction 10.

(22) The door construction 10 may also comprise suitable supports (not shown), such as supports 17 shown in FIG. 1, for supporting the bottom surface of the support piece 9. These supports may be formed to the frame 3 of the filling device 1 as the supports 17 shown in FIG. 1, to the door construction 10, or to both.

(23) The upper part 11 b of the lower support portion 11 of the door construction is preferably also equipped with one or more magnets (not shown) than enhance the fixing of the aerosol container 2, which are typically of suitable metallic material, to the lower support portion 11 of the door construction 10. Further, these magnet(s) also help to keep a collection vessel at its place for receiving the detached piston head 7 when the piston head need to be changed, for example.

(24) The above discussed door construction 10 allows for improved preparation and implementing of the filling process with a filling device 1, where the possibility for spilling of the liquid to be transferred before and during of the filling process is advantageously minimized.

(25) The specific exemplifying embodiment of the invention shown in figures and discussed above should not be construed as limiting. A person skilled in the art can amend and modify the embodiment of the invention described in many evident ways within the scope of the attached claims. Thus, the invention is not limited merely to the embodiment described above.