IL109789A

IL109789A - Lid for plastic container

Info

Publication number: IL109789A
Application number: IL10978994A
Authority: IL
Inventors: Moshe Straussman
Original assignee: Emraz Ltd
Priority date: 1994-05-25
Filing date: 1994-05-25
Publication date: 1996-08-04
Also published as: AU2652195A; GB9624194D0; DK134296A; WO1995032128A1; GB2303365B; GB2303365A; IL109789A0

Description

LID FOR PLASTIC CONTAINER LID FOR PLASTIC CONTAINER FIELD OF THE INVENTION The present invention relates to plastic containers with inwardly projecting rims and particularly to lids for sealing such The invention also relates to a method of sealing plastic containers to prevent spillage when dropping the container or knocking it BACKGROUND OF THE INVENTION Traditionally paint cans were made of metal having an inverted with a metal plug lid providing the In recent years plastic paint containers have come on the which provide obvious advantages such as dent resistance and make them suitable for both water and solvent based These containers are also easier to One recent US discloses such a plastic container having inwardly projecting This type of container has an advantage in that it provides a larger area for labelling or advertising and furthermore prevents liquid in the container from splashing over when moving the as for example from the filling station to the lidding One problem that these containers have not yet overcome is that they are prone to leakage when they are dropped or knocked This is due to the fact that the generally round body of the container is distorted upon impact with the thus also distorting the configuration of the mouth of the for example from a round shape to an oval with a longer diameter in one The on the other which is subjected to pressure from inside the does not distort in the same thus leaving an opening between the lid edge and the container wall for the contents to leak out and often the lid pops out completely spilling the whole One solution to this problem is to make the inwardly pointing rim to point more but this would make it difficult to close and open the SUMMARY OF THE INVENTION It is the object of the present invention to provide plastic containers with inwardly projecting rims which are sealed more securely to prevent their opening and spilling upon particularly lateral It is a further object of the invention to provide plastic containers which are sealed and opened more easily Yet another object of the invention is to provide lids for plastic containers with inwardly projecting rims which provide a better seal and render the container on especially lateral Still another object of the invention is to provide a method for sealing containers to prevent spillage on dropping or falling over to the BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood and appreciated from the following detailed description taken in conjunction with the in Figure 1a is a sectional elevational view of a lidded container in accordance with the prior Figure 1b is a detailed view of section A in Figure Figure 2a is a sectional elevational view of a lidded container in accordance with the Figure 2b is a detailed view of section B in Figure and Figure 3 is a section view of a lid closure in accordance with an alternative embodiment of the invention DETAILED DESCRIPTION OF THE INVENTION Referring now to Figures 1a and these represent a prior art container generally round in configuration and having a lid The closure between lid 2 and container is as Wall 16 of the container 10 has an upper rim 12 extending around the inner wall of the This rim 12 is thicker than wall 16 and includes a top edge 22 and a lower lip which forms a groove 9 in the rim Lid 2 comprises a flat round central portion from which there extends around the entire lid an edge portion 14 which is generally trough This edge portion 14 comprises an inner wall 15 and an outer wall which are connected at the bottom of the walls and by a fixed bridging element A circumferential flange 6 at the lower end of wall 17 is adapted to engage the lower lip 8 of rim The lid 2 is thus closed on the container 10 by pressing the lid 2 downwards into the thereby snapping flange 6 under lip 8 and at the same time contacting upper end 20 of wall 17 with upper edge 22 of rim To ensure a tight a sealing ring 18 is provided on wall which presses against rim when the lid is This particular configuration of the edge portion 14 with a fixed element 19 bridging walls and provides sufficient resilience so that flange 6 can undergo lateral displacement either when closing the lid by pressing downward or by prying the lid open with a sharp instrument inserted between the upper end 20 of the outer wall and top edge 22 of rim This prior art container has serious one of which is that the container is not when knocked over or falls from a stack of containers and impacts the In such a the contents of the container press against the inner surface of lid creating a force pushing the lid outward from the This outward force causes the edge portion 14 to flex and pull walls 15 and including flange inwardly into the interior of the disengaging it from lower lip 8 of rim thereby creating an opening for spillage of the container If the force against the container lid from inside the container is sufficiently the entire lid is subject to being pushed One way of overcoming this problem is by making the rim creates a different by making it more difficult to open the lid under normal use conditions or to close the lid after filling the container in the or reclosing the lid after use the first Referring now to Figures 2a and there is illustrated a container with a lid in accordance with one embodiment of the present The container is the same as shown in Figure 1a having an internal rim with lower lip The is In this embodiment the lid 2a has a similarly flat round central portion 4 which is connected to a generally edge portion 14a via circumferential hinge This edge portion 14a is different from the prior art and enables easier opening and closing of the container than was previously possible and furthermore provides resistance to accidental opening of the lid and spillage when the container is subjected to for example falling or being knocked The edge portion of lid 2a is comprised of a rigid inner wall 15a and exterior wall 17a with a diagonal bridging element 19a between This bridging element 19a is hingedly connected at its terminal ends 38 and 40 to walls 15a and 17a Wall 17a in the present instance can be made thinner than wall 17 of the prior art lid shown in Figures 1a and The inner wall 15a is made rigid by providing radial reinforcing ribs bridging element 19a is made rigid by providing periodic reinforcing ribs The outer wall 17a comprises an upper lip flange 6a and sealing ring 18a similar to the corresponding elements in Figures 1a and The lid of this invention as illustrated in Figures 2a and 2b is easier to close and to open and is more resistant to spilling of contents when the container is subjected to such as by especially lateral impact on the side of the This is because when the contents of the container 10 upon impact exert a force on the lid 2a from inside the the rigid wall 15a is displaced upwardly via hinge 5 towards the opening of the interior of the container The outer wall remains firmly attached to the rim because diagonal bridging element which is connected to wall 15a by means of hinge 38 and to wall by means of hinge translates the upward force exerted on wall to a lateral component and adjusts itself between walls 15a and 17a to provide lateral outward displacement of flange 6a which remains engaged with lip 8 to keep the seal between lid 2 and wall 16 even if side wall 16 were to be displaced outwardly from the the hinged diagonal bridging element 19a would displace wall in the same outward while maintaining its grip on rim Wall 15a has at its approximate center a ledge 13 with a vertically downward extending rib 23 circling the under side of the The circumferential rib together with the radial rib provide the required rigidity to wall Step 13 is more for design purposes for better stacking of lids and not essential to the invention as is shown in Figure which shows another embodiment of the lid having a straight inner wall It is to be appreciated by persons skilled in the art that the scope of the present invention is not limited to what has been shown and described above merely by way of The scope of the present invention is limited rather solely by the claims which insufficientOCRQuality

Claims

109789/2 C L A I M S

1. A lid for containers having an inner rim along the perimeter of the container wall, said lid comprising: a substantially flat central portion, a trough-shaped edge portion comprising a rigid inner wall, a rigid outer wall and a rigid bridge element connecting the inner and outer walls, the central portion, inner wall, outer wall and bridge element having respective defined thicknesses, means disposed on the outer wall for sealingly engaging the inner rim of the container, characterized in that the central portion of the lid is integrally and flexibly hinged to the inner wall of the edge portion, and the bridge element is integrally and flexibly hinged to both the inner wall and the outer wall, said integral and flexibly hinges are of a thickness less than the respective thicknesses of the elements that they connect, so that when a vertical force is applied to the lid from inside the container, the rigid bridge element translates the vertical force exerted on the under side of the lid into a lateral force exerted on the rigid outer wall of the edge portion, thus maintaining the seal between lid and container.

2. A lid as in claim 1 wherein the inner wall is shorter than the outer wall and the bridge element connecting these walls is diagonal. 9 109789/2

3. A lid as in claim 1 wherein the inner wall comprises reinforcing rings.

4. A lid as in claim 1 wherein the bridging element comprises integrally molded reinforcing ribs.

5. A lid as in claim 1 wherein the outer wall comprises a sealing ring.

6. A sealed container comprising a container having a rim along the inner perimeter of the container wall and a lid comprising a substantially flat central portion, a trough-shaped edge portion comprising a rigid inner wall, a rigid outer wall and a rigid bridge element connecting the inner and outer walls, the central portion, inner wall, outer wall and bridge element having respective defined thicknesses, means disposed on the outer wall for sealingly engaging the inner rim of the container, characterized in that the central portion of the lid is integrally and flexibly hinged to the inner wall of the edge portion, and the bridge element is integrally and flexibly hinged to both the inner wall and the outer wall, said integral and flexibly hinges are of a thickness less than the respective thicknesses of the elements that they connect, so that when a vertical force is applied to the lid from inside the container, the rigid bridge element translates the vertical force exerted on the under side of the lid into a lateral force exerted on the rigid outer 109789/ 1 - 10 - wall of the edge portion, thus maintaining the seal between lid and container.

7. A method of sealing a container having an inner rim along the perimeter of the container wall, with a plastic lid, comprising snap fitting a lid onto a container having an inner rim along its perimeter said lid comprising a substantially flat central portion, a trough-shaped edge portion comprising a rigid inner wall, a rigid outer wall and a rigid bridge element connecting the inner and outer walls, the central portion, inner wall, outer wall and bridge element having respective defined thicknesses, means disposed on the outer wall for sealingly engaging the inner rim of the container, characterized in that the central portion of the lid is integrally and flexibly hinged to the inner wall of the edge portion, and the bridge element is integrally and flexibly hinged to both the inner wall and the outer wall, said integral and flexibly hinges are of a thickness less than the respective thicknesses of the elements that they connect, so that when a vertical force is applied to the lid from inside the container, the rigid bridge element translates the vertical force exerted on the under side of the lid into a lateral force exerted on the rigid outer wall of the edge portion, thus maintaining the seal between lid and container. AGENT FOR APPLICANT