CONTAINER AND LID

Abstract: The invention relates to a container and lid, of which the container at least is made of plastic and comprises a container base (1) and a vertival container wall (2), the rims of the container and the lid being provided with cooperating sealing and locking devices. The sealing and locking devices of the lid consist of a lower lid-wall section (11), which, when the lid is closed, is rotationally symmetrical, and a rotationally symmetrical upper lid-wall section (14). The surface areas of the horizontal cross-sections of the lid-wall sections increase in upward direction and the lid-wall sections being separated all round by the mouth of a groove (13) directed upwards, of which the inside and outside groove walls pass into the lower and upper lid-wall sections, respectively. The sealing and locking devices of the con­ tainer consists of a groove-shaped channel (3), open at the top, applied along the rim of the container, with a vertical outside channel wall (4), a vertical inside channel wall (7) and a channel base (6), the inside face of the outside channel wall being provided with a snap rib (5), such that an upper part of the inside channel wall of the container is tightly enclosed in the groove of a lid placed on the container, and the free rim of the upper lid-wall section grips beneath the snap rib with some tension.

Description: The invention relates to a container and lid, of which the container at least is made of plastic and comprises a container base and a vertival container wall, the mouth of the container and the lid being provided with cooperating sealing and locking devices. Numerous similar container-and-lid systems have been suggestd in the last few decades and have become known from, for example, the German Offenlegungsschrift 1936687. The use of plastic containers and lids for packaging purposes has increased enormously, in line with the development of machines designed to automatically fill the containers and fit the lids onto the containers. In this final stage of the process, the lids are often dropped horizontally from a supply storage to fall loosely on the filled containers, upon which the lids are pressed tightly onto the containers in a next stage. A disadvantage of the known container-and-­ lid systems is that the lids, when dropped loosely onto the con­ tainers, do not centre sufficiently on the containers, thus causing disturbances when they are pressed down into place, which, at the rate at which the containers are at present filled and provided with lids, leads to considerable wastage. The aim of the invention is to provide a container and lid, of which the lid centres excellently on the container and which systems ensures that when the lid is pressed down onto the container, the container and lid are sealed and locked in an excellent manner with respect to the present state of the art, which two functions can be performed optimally and separately. To achieve this aim, the sealing and locking devices of the lid at least consist of a lower lid-wall section, which, when the lid is closed, is rotationally symmetrical, and a rotationally symmetrical upper lid-wall section, the surface areas of the horizontal cross-­ sections of which lid-wall sections increase in upward direction, the lid-wall sections being separated all round by the mouth of an upwardly directed groove, of which the inside and outside groove walls pass into the lower and upper lid-wall sections, respectively, and the sealing and locking devices of the container at least consists of a groove-shaped channel, open at the top, applied along the rim of the container, with a vertical outside channel wall, a vertical inside channel wall and a channel base, of which the inside face of the out­ side channel wall is provided with a snap rib, such that an upper part of the inside channel wall of the container is tightly enclosed in the groove of a lid placed on the container, and the free rim of the upper lid-wall section grips beneath the snap rib with some tension. A sealing and locking device for a container and lid designed as described above has a lid which makes optimum use of the centering possibilities of the part of the lid available for that purpose. Even lids placed in a relatively decentralized position with respect to the rim of the container will centre correctly when pressed, which process is then followed by the pressing down of the lid, sealing and locking. The container is sealed by locking the upper part of the inside chan­ nel wall in the groove. In this manner an attractive, wide sealing joint is obtained, which corresponds to the inner circumference of a cross-section perpendicular to the groove. The groove presents the additional advantage of allowing some tolerance in the dimensioning of the lid, which is of particular importance in the injection moulding of plastic for obtaining a good fit of the system's sealing and locking devices. Another advantage of the lid is that the vertical lid wall is not only functional in centering, but also exerts a downward force on the entire lid, once its free peripheral rim has been inserted below the snap rib, which improves the quality of the sealing system. A further advantage of the lid is that its dimensions are the same when placed on any of the different embodiments of the container to be discussed below, which means that the same lid can be used in all cases. The design of the sealing and locking system presents the substantial advantage that, when the container is closed, there is still some free space between the upper lid-wall section and part of the inside face of the outside channel wall, the inside channel wall and the channel base. This free space can be made accessible from out­ side by applying one or more apertures in the outside channel wall and/or in the upper lid-wall section, between the groove and the free rim of the upper lid-wall section. Through these apertures and via the free space, a tool can be inserted beneath the upper lid-wall section for the purpose of lifting the lid. According to a first embodiment of the container according to the invention, the outside channel wall forms part of the vertical container wall. The fact that the channel is then situated on the inside of the vertical container wall presents the advantage that the container has an entirely smooth outer face, which can be printed as is required of, particularly, the containers used in the paint industry. The system's high sealing and locking quality also renders this type of container and lid extremely suitable for packaging paint. By giving the vertical container wall a substantially cylindrical shape, this embodiment can also be used on existing filling lines. In a second embodiment of the container according to the invention, the inside channel wall forms part of the vertical con­ tainer wall. The fact that the channel is then situated on the outside of the vertical container wall enables nesting of containers whose horizontal cross-section gradually increases from the container base to the rim, which presents advantages in transporting empty containers. Such containers are used for latex paints in particular, because their relatively wide openings afford easy access for broad brushes. In a third embodiment of the container according to the invention, the vertical container wall, whether or not cylindrical, butts up to the base of the channel walls. The situation of the channel on top of the vertical container wall constitutes a compromise between the first and second embodiments and their respective advantages. This embodiment presents a considerable advantage in pressing down the lid, because the forces are then transmitted better via the vertical container wall to the solid underground. Furthermore, the undercut on the inside of the container is less than in the first embodiment, which may present an advantage in terms of moulding. In addition, this container can hold more. The snap rib is situated with advantage near the free edge of the outside channel wall. The snap rib, forming a thickened ridge, thus renders the rim, which is sensitive to damage, more resistant. The rotationally symmetrical lower lid-wall section and the rotationally symmetrical upper lid-wall section may be situated in the same conical plane to create a practically uninterrupted sliding sur­ face, which facilities centering. It may also be advantageous to radially shift one of the two conical planes containing the lower and the upper lid-wall sections with respect to the other, to this create a stop ridge. In particular, it may be advantageous to shift the second conical plane, containing the upper lid-wall section, radially inward with respect to the first conical plane, containing the lower lid-wall section. When, in this case, a lid that is out of alignment is pressed down from the highest point, the diametrically opposite side will be pushed up until it reaches the stop ridge, which enables the inside channel wall to slide into the groove more easily. The rotationally symmetrical lower lid-wall section and the rotationally symmetrical upper lid-wall section may lie in the same spherical plane, which optimizes the sliding of these walls in the circular free edge of the inside channel wall. This too creates a practically uninterrupted sliding surface which facilitates centering. For the same reasons as indicated above in the case of the conical planes, it may be advantageous to radially shift the spherical planes with respect to each other. In particular, it may be advantageous to shift the second spherical plane, containing the upper lid-wall sec­ tion, radially inwards with respect to the first spherical plane, con­ taining the lower lid-wall section. The already-mentioned free space in the channel below the upper lid-wall section can also be used to accomodate the pins of a wire handle, which pins can then be inserted through two apertures applied diametrically opposite each other in the outside channel wall. In this manner the use of lugs projecting outwards and consequently getting in the way is avoided. The container and lid may both be of plastic, manufactured by injection moulding suitable (co)polymers like polymers of ethylene, propene, copolymers of ethylene and propene or mixtures of those substances. It may be advantageous to manufacture the lid from a dif­ ferent plastic than that used for the container. For example, it may be desirable to manufacture the container from a relatively stiffer plastic than that used to manufacture the lid to obtain a better fit of the inside channel wall in the groove. The lid may be made of a metal, which, for example, presents the advantage that if the upper lid-wall section contains the above-­ mentioned aperture through which a tool may be inserted, the lid is damaged less easily when it is lifted off. A metal lid may present the additional advantage of finding acceptance more readily as a form of paint packaging in the paint industry, because the filling lines need be adjusted only in part. A similar combination of container and lid may also be accepted sooner by industry and consumers for psychologi­ cal reasons. The invention will be further elucidated with reference to some examples of embodiments illustrated in the drawing. In the drawing: Fig. 1 represents an axial cross-section of one half of a container and lid in open condition according to the invention; Fig. 2 represents an axial cross-section of one half of the con­ tainer and lid shown in Fig. 1 in closed condition; Fig. 3 represents the lid shown in Fig. 1, viewed from above; Fig. 4 represents the container shown in Fig. 1, viewed from above; Fig. 5 represents an axial cross-section of one half of a container and lid in open condition of a second embodiment according to the invention; Fig. 6 represents an axial cross-section of one half of the con­ tainer and lid shown in Fig. 5, viewed from above; Fig. 7 represents the container shown in Fig. 5, viewed from above; Fig. 8 represents an axial cross-section of one half of a container and lid in open condition of a third embodiment according to the invention; Fig. 9 represents an axial cross-section of one half of the con­ tainer and lid shown in Fig. 8 in closed condition; Fig. 10 represents the container shown in Fig. 8, viewed from above; Fig. 11 gives an enlarged representation of the part marked by a dashed rectangle XI in Fig. 2; Fig. 12 gives an enlarged representation of the part marked by a dashed rectangle XII in Fig. 6 and Fig. 13 a-d give schematical representations of some embodiments of the lid according to the invention. The reference numbers used in the figures always refer to the same parts. Figure 1 shows a container with a base 1, a vertical con­ tainer wall 2, a groove-shaped channel 3 with an outside channel wall 4, a snap rib 5, a channel base 6, an inside channel wall 7 and a mouth 8. Parts 3, 4, 5 and 6 constitute the sealing and locking devi­ ces of the container. In addition, Figure 1 shows a lid, belonging to the container, with a middle section 9, which, via an angle 10, passes into a rotationally symmetrical lower lid wall section 11 and a rota­ tionally symmetrical upper lid-wall section 14. The surface areas of the horizontal cross-sections of wall-sections 11 and 14 both increase in upward direction. In Figure 1 the lid-wall sections lie in the same conical plane. The lid-wall sections are separated from each other by the mouth of a groove 13, whose inside and outside groove walls pass into the lower 11 and upper 14 lid-wall sections, respectively. The upper lid-wall section 14 ends in a free peripheral rim 12. The dif­ ferent embodiments of the lid are further elucidated with the help of Figure 13. Even if the centre lines of lid and container are not in alignment, that is, even when the lid is out of alignment and/or in a decentral position, the lid will automatically assume the position shown in Fig. 2 when pressed down. In this position the inside channel wall 7 is enclosed in groove 13 of the lid, thus sealing the con­ tainer, and the free peripherical rim 12 grips below snap rib 5, thus locking the lid. The dimensioning may be such that the upper lid-wall section 14 between the free peripheral rim 12 and the groove 13 is under some tension, as a result of which the lid is held firmly on the container. Figure 3 shows the lid 11 belonging to the container illustrated in Figs. 1 and 2, viewed from above, which figure also applies to the embodiments of the container according to Figures 5 and 6, and Figures 8 and 9. Figure 4 gives a detailed representation of an open con­ tainer, viewed from above. The working of the embodiment according to Figures 5, 6 and 7, as well as that of the embodiment according to Figures 8, 9 and 10 will be clear after the above explanation of the embodiment to Figures 1, 2, 3 and 4. The provisions that have been taken to enable the lid to be opened are shown for two embodiments in Figures 11 and 12. Figure 11 shows an aperture 15, one or more of which may have been applied in the outside channel wall 4. The free space 3 bounded by the upper lid-­ wall section 14, the outside channel wall 4, the channel base 6 and part of the inside channel wall 7, is now accessible from outside via the aperture 15, through which a tool 16, for example a screwdriver, can be inserted beneath the part of the lid indicated by reference number 17. The lid can then be lifted from the container by means of the lever action of the tool 16 in the direction indicated by A. Figure 12 shows the free space 3 made accessible by the application of one or more apertures 18 in the upper lid wall section 14. The place of tool 16 can be inserted through aperture 18 to near the part of the lid indicated by reference number 17, upon which the cover can be lifted from the container by means of the lever action of the tool 16 in the direction indicated by B. The aperture 18 is preferably designed as a U-shaped slot in the free rim 12. See also Fig. 3. When the lid is lifted, the snap rib 5 being pressed outwardly the ends of the U-shaped slot will move to above the snap rib, upon which the screwdriver can be moved along the circumference of the snap rib to completely loosen the lid. The apertures indicated in Figures 11 and 12 by 18 and 19, respectively, are intended to accommodate the pins of wire handles, not shown here. Figure 13 gives a schematical representation of some embodi­ ments of the lid, of which Figure 13a corresponds substantially to Figure 2. In Figures 13 a and b the lower lid-wall section 11 and the upper lid-wall section 14 lie in the conical planes indicated by I and II, respectively, which conical planes belong to the same conical plane in Figure 13a and are separated by the mouth 20 of a groove 13, whose inside groove wall 21 and outside groove wall 22 pass into the lower lid wall section 11 and the upper lid wall section 14, respec­ tively. In Figure 13b conical plane II, containing upper lid-wall section 14, is radially shifted inwards with respect to conical plane I, containing the lower lid-wall section. Although the conical planes are not parallel in Figure 13b, this is indeed possible, with the same advantages of the radial shift. Figure 13c shows an embodiment in which the lower lid-wall section 11 and the upper lid-wall section 14 are situated in the spherical planes III and IV, respectively, of the same spherical plane with a radius R. For reasons of clearness, the parts have not all been indicated by reference numbers here. Figure 13d shows an embodiment in which the lower lid-wall section 11 and the upper lid-wall section 14 are situated in a spheri­ cal plane III with radius R₂ and a spherical plane IV with radius R₁, respectively, with R₁ being smaller than R₂ and the radii having the same centre (not shown), so that the spherical plane IV presents a radial shift inwards with respect to the parallel spherical plane III. This can also be achieved by using radii of equal lengths with dif­ ferent centres. To prevent stacked containers from shifting with respect to one another, it is possible to use at least one of the channel walls with advantage by causing it to project slightly above the surface of the container, being either closed or open, to thus create an eleva­ tion, and to provide the base of a container with a ribbed pattern and/or embossed projections, into which the elevation fits. The eleva­ tion is preferably applied to the channel wall coinciding with the wall of the container to enable the forces to be more easily diverted to the base of a stack.

Claims: 1. Container and lid, of which the container at least is made of plastic and comprises a container base and a vertival container wall, the rims of the container and the lid being provided with cooperating sealing and locking devices, characterized in that, the sealing and locking devices of the lid at least consist of a lower lid-wall section, which, when the lid is closed, is rota­ tionally symmetrical, and a rotationally symmetrical upper lid-­ wall section, the surface areas of the horizontal cross-sections of which lid-wall sections increase in upward direction, the lid-­ wall sections being separated all round by the mouth of a groove directed upwards, of which the inside and outside groove walls pass into the lower and upper lid-wall sections, respectively, and that the sealing and locking devices of the container at least consists of a groove-shaped channel, open at the top, applied along the rim of the container, with a vertical outside channel wall, a vertical inside channel wall and a channel base, the inside face of the outside channel wall being provided with a snap rib, such that an upper part of the inside channel wall of the container is tightly enclosed in the groove of a lid placed on the container, and the free rim of the upper lid-wall section grips beneath the snap rib with some tension. 2. Container and lid according to claim 1, characterized in that, the inside channel wall forms part of the vertical container wall. 3. Container and lid according to claim 1, characterized in that, the inside channel wall forms part of the vertical container wall. 4. Container and lid according to claim 1, characterized in that the vertical container wall butts up to the base of the channel at a point between the inside channel wall and the outside channel wall. 5. Container and lid according to any one of claims 1-4, charac­ terized in that the snap rib is situated near the free edge of the outside channel wall. 6. Container and lid according to any one of claims 1-5, charac­ terized in that, the lower lid-wall section and the upper lid-wall section lie in the same conical plane. 7. Container and lid according to any one of claims 1-5, charac­ terized in that, the lower lid-wall section lies in a first coni­ cal plane and the upper lid-wall section lies in a second conical plane and the first conical plane is radially shifted with respect to the second conical plane. 8. Container and lid according to claim 7, characterized in that the second conical plane is shifted inward with respect to the first conical plane. 9. Container and lid according to any one of claims 1-5, charac­ terized in that the lower and the upper lid-wall section both lie in the same spherical plane. 10. Container and lid according to any one of claims 1-5, charac­ terized in that the lower lid-wall section lies in a first spheri­ cal plane and the upper lid-wall section lies in a second spheri­ cal plane, the first and second spherical planes being radially shifted. 11. Container and lid according to claim 10, characterized in that the second spherical plane is radially shifted inwards with respect to the first spherical plane. 12. Container and lid according to any one of claims 1-11, charac­ terized in that the outside channel wall is provided with one or more apertures through which a tool may be inserted in order to lift the lid off the container. 13. Container and lid according to any one of claims 1-12, charac­ terized in that the upper lid-wall section is provided with one or more U-shaped slots between the groove and the free peripheral rim, through which a tool can be inserted for the purpose of lifting the lid off the container. 14. Container and lid according to any one of claims 1-13, charac­ terized in that the outside channel wall is provided with two apertures situated diametrically opposite one another for the attachment of a handle. 15. Container and lid according to any one of claims 1-14, charac­ terized in that the horizontal cross-section of the container gra­ dually widens from the base of the container to the rim, to enable nesting of the containers. 16. Container and lid according to any one of claims 1-15, charac­ terized in that both are made of plastic. 17. Container and lid according to claim 16, characterized in that the conainer is manufactured from a different plastic than that used for the lid. 18. Container and lid according to any one of claims 1-14, charac­ terized in that the lid is made of metal. 19. Container and lid as described and/or claimed and/or elucidated with reference to the drawings.

Inventors: MARKUS, ADRIANUS JOHANNES WILHELM
Applicants: PACKAGING & CONTAINER MANUFACTURERS B.V.
Application year: 1987
Main classification: B65D43
IPC codes: B65D43