A container with a lid

Abstract: A container (2) with a lid (4) consisting of plastic material in which the edge portion (12) of the lid (4) has a peripheral, downwardly directed edge flange (28) sealingly enclosing an edge portion (10) of the container positioned at the opening thereof. The edge flange has at a surface which faces said edge portion an inwardly directed, continuous projection (34) which engages a downwardly facing engagement surface (12) of the edge portion of the container. In order to facilitate the removal of the lid from the container the lid has immediately above the inwardly directed, continuous projection a hinge provided by a material reduction (36) and the lower, free edge surface (33) of the edge flange is positioned immediately beneath the inwardly directed, continuous projection (34).

Description: The present invention relates to a container with a lid consisting of plastic material. Containers of different kinds and for different purposes, for example plastic containers for paint and food-stuffs, are often closed by means of a lid consisting of plastic material, the lid being pressed onto the edge portion of the container. Thereby it is common that the edge portion of the lid has a peripheral, downwardly directed edge flange which encloses the edge portion at the opening of the container and has at a surface opposed to this edge portion an inwardly directed, peripheral projection which for releasably retaining the lid to the container engages beneath the downwardly directed engagement surface at said edge portion of the container. There exist a number of contradictory desires when designing lids of this kind. For example it is desirable that the edge flange of the lid has a firm engagement with a certain pretension around the edge portion of the container for making sure that the lid is retained during transport and storage and that a sufficient tightness of the closure of the container is maintained. The desire of a firm engagement and pretension between the edge flange of the lid and the edge portion at the opening of the container is opposite to the desire that it shall be easy to remove the lid when the container shall be opened. Also in respect of the hardness of the plastic material of the lid there are certain contradictory desires. Thus, it is desirable that the lid consists of a relatively soft plastic material to comply with the desire of good tightness and easiness to remove the lid while it is desirable to use a relatively hard plastic material for the manufacturing of the lid so as to provide the lid with high strength at the stacking of the containers provided with the lids. A relatively hard plastic material for the manufacturing of the lid also makes it possible to manufacture the container and the lid of one and the same plastic material which is a substantial advantage in recovering the plastic material. Many different lid constructions are known for solving the different problems existing with regard to tightness, stackability, easy removal and so on. The Swedish Patent No 8005819-1 describes a container with a lid, wherein the edge portion of the lid is designed for solving the sealing problem in connection with containers for paint of the type which is positioned in a shaking machine for blending the paint when tinting the paint to different tones. According to this patent the tightness problem is solved by providing between the container and the lid a large number of separate sealing zones. In a lid of this kind the edge portion of the cover has a downwardly directed edge flange with a peripheral projection which for releaseably retaining the lid to the container engages beneath a downwardly directed engagement surface at the edge portion of the container. Below the peripheral projection the edge flange has an edge portion which is adapted to be grasped when the lid shall be removed. The lid according to the invention presents a good sealing against the edge portion of the container but has the drawback of being difficult to remove from the container. When grasping the edge portion positioned below the peripheral projection with the fingers for removing the lid the edge portion is drawn radially inwards at the rest of the periphery of the lid which provides that the engagement between the peripheral projection of the lid and the downwardly facing engagement surface of the edge portion of the container can be overcome only with great difficulties when removing the lid. The difficulties can be set aside by manufacturing the lid from a relatively soft plastic material but this brings about the drawbacks discussed above with regard to the requirement for a certain strength of the lid when stacking containers and the requirement of separating lids and containers from each other when recovering the plastic material. In another previously known type of container with a lid of the kind described the lid has at its downwardly directed flange an upwards foldable edge portion forming a so called bistable locking flange. When said edge portion is folded upwards the peripheral projection is completely or partially released from engagement with the downwardly directed engagement surface of the edge portion of the container and it is thereupon relatively simple to remove the lid from the container and also to reposition the lid thereon. Containers with a lid of this kind are previously known from for example the Swedish Patent Specification No 8106169-9 and the Danish Patent Specification No 155 123. In the lid according to the last mentioned patent specifications the downwardly directed, upwards foldable locking flange is divided in at least two sections by means of notches which facilitate the upwardly directed folding of the locking flange prior to the removal of the lid. This makes it possible also to provide the cover with a tamper-proof closure by providing thin material sections at the notches which sections are broken when the locking flange is folded upwards. A common drawback of the previously known lid constructions having a so called bistable locking flange is that it can be relatively time consuming and difficult to fold up the locking flange as a preparation for the removal of the lid. Especially in the professional use, for example in painting work, it is desirable that the lid of a plastic container shall be adapted to be teared off in a rapid and simple way. It is in this connection common that no reclosure of the containers is required. Thus, the object of the present invention is to solve the problem of providing a container with a plastic material lid, wherein the lid in spite of maintaining the requirement for tightness can be torn from the container in a simple way when the container shall be opened. This problem is to a certain extent solved by means of a container with a lid of the type described in for example US-A-4 024 976. In a container with a lid of this type the lid has immediately above a peripheral inwardly directed projection a hinge provided by material reduction and the lid has the lower free edge surface of the edge flange positioned immediately beneath the peripheral, inwardly directed projection. However, for removing a lid of this kind it is still necessary to manipulate the lid flange for which reason the container with a lid according to US-A-4 024 976 does not present a complete solution to the problem of providing a container with a lid wherein the lid can be grasped and teared off from the container in one single operation. Said problem is solved by means of a container with a lid having immediately above a peripheral inwardly directed projection a hinge provided by material reduction and having the lower free edge surface of the edge flange positioned immediately beneath the peripheral, inwardly directed projection, wherein the container with a lid is in accordance with the invention characterized in that the peripheral, downwardly extending edge flange of the lid is over at least one region of its periphery provided with strengthening means for providing a gripping portion. When lid of a container with a lid of this kind shall be removed from the container the gripping portion of the lid is grasped and displaced upwardly which provides that the inwardly directed projection pivots outwardly around the hinge positioned immediately above the projection without any resistance from any portion of the edge flange positioned beneath the projection, the pivoting movement taking place as a wave motion following the container flange away from the gripping position until the entire lid has been removed. The gripping portion constituted by the strengthening means provides that the lid can be removed from the container without any manipulation of the edge flange of the lid but only by grasping the gripping portion and tearing off the lid in one single operation. The lid can be designed so as to have a relatively firm bias towards the edge portion of the container which in turn provides for better tightness. It is also possible to provide the lid with larger and more projecting projections also providing for better tightness while it is at the same time possible to manufacture the lid from a relatively hard plastic material allowing that several containers are stacked on each other and that the container and the lid are manufactured from one and the same plastic material. The strengthening means of the lid can for example consist of radially directed ribs extending across the hinge. Preferably the edge flange of the lid forms an outer wall of a downwardly open, continuous channel which sealingly receives the edge portion of the container, positioned at the opening thereof, said wall being provided above the hinge formed by the material reduction with strengthening means, for example in the form of radially extending ribs. In order to prevent that the lid is inadvertently removed from the container as a result of pressure applied to the edge flange of the lid the container of one embodiment of the invention is provided with a radially projecting protective flange positioned immediately beneath the lower free edge surface of the edge flange of the lid. Preferably the radially projecting protective flange has at least one recess for providing an area in which the edge flange of the lid can be grasped for allowing the intentional removal of the lid from the container. It is suitable to form the protective flange as a lower, radially projecting portion of a skirt projecting downwardly-outwardly from the wall of the container, the downwardly directed engagement surface being provided on a peripheral projection positioned above said protective flange. Some different embodiments of the invention shall be described in the following with reference to the accompanying drawings. Figs. 1a and 1b are a side view and a plan view, respectively, of an embodiment of a container with a cover according to the invention. Fig. 2 is a section on an enlarged scale along line II-II in Fig. 1b. Fig. 3 is a section on an enlarged scale along the line III-III in Fig. 1b. Fig. 4 is a view corresponding to Fig. 1b of the container with a cover when the removal of the cover has been initiated. Fig. 5 is a section along line V-V in Fig. 4 on an enlarged scale. FIg. 6 is a section on line VI-VI in Fig. 4 on an enlarged scale. Fig. 7, 8, 9, 10 and 11 are sections corresponding to the section of Fig. 1 on an enlarged scale of modified embodiments of containers with covers according to the invention. Fig. 12 is a plan view of a peripheral part of the container of the embodiment shown in Fig. 12. Figs. 1a and 1b show a container 2 having a lid 4. The container and the lid consist of a plastic material. The container 2 has in a conventional way a bottom 6 and a somewhat conical side wall 8. The side wall 8 has an edge portion 10 which is designed so as to sealingly engage with an edge portion 12 of the lid 4. In the embodiment shown in Fig. 1 - 6 the edge portion 10 of the container is constituted by an upper sealing edge 14 and a bead 16 radially projecting at some distance from the edge and having a downwardly directed edge portion 18. The downwardly directed edge portion 18 forms a downwardly facing engagement surface 20. The edge portion 10 of the container is enclosed by the edge portion 12 of the lid, which edge portion 12 forms a downwardly open, continuous channel 22 defined by an inner wall 24, an upper wall 26 and an outer wall which forms an edge flange 28. At its inner surface the wall 26 has a centrally positioned, downwardly extending, continuous bead 30 which together with the wall 24 defines a channel 32 which is sealingly engaged by the sealing edge 14 of the container. The edge flange 28 of the lid 4 has at its lower, free edge 33 a continuous inwardly directed projection 34 which engages beneath the downwardly directed edge portion 18 of the bead 16 and thus engages the downwardly facing engagement surface 20 of the edge portion 18. Between the projection 34 and the portion of the edge flange 28 positioned above the projection there is arranged an inner peripheral groove 36 forming a hinge allowing a certain pivoting movement of the lower portion of the edge flange 28 on which the projection 34 is positioned. A part of the periphery of the lid is provided with radially extending ribs 38 extending across the hinge formed by the groove 38 so that the projection 34 of the peripheral portion of the edge flange 28 on which the ribs 38 are provided is rigidly connected with the portion of the edge flange 28 positioned above the hinge. In accordance therewith the peripheral portion provided with the ribs will form a gripping portion which as described in the following is used for facilitating the removal of the lid from the container. At its inner surface the edge portion 12 of the lid has a number of strengthening ribs 40 distributed around the entire periphery of the lid for stabilizing the portion of the edge flange 28 positioned above the groove 36 around the entire lid. The lid can easily be removed from the container by grasping with the hand the portion of the lid provided with the ribs 38 in an upwardly directed movement, the portion of the cover provided with the ribs 38 being displaced outwards to the position shown in fig. 5 in which the projection 34 is locally out of engagement with the downwardly facing surface 20 of the portion 18. At the continued pulling of the portion of the cover provided with the ribs 38 the portion of the edge flange 28 provided with the projection 34 will locally on both sides of the portion provided with the web pivot outwards to a position in which the projection 34 is out of engagement with the downwardly facing engagement surface 20. This pivotal motion will as a wave be displaced in opposite directions from the portion of the edge flange provided with the ribs 38 as appears from fig. 4 until the outwardly pivoted sections meet at the diametrically opposite side of the lid and the lid has thereby been completely removed from the container. Because of the groove 36 and the hinge provided thereby and because of the fact that the edge flange 28 has its lower, free edge surface 32 positioned immediately beneath the inwardly directed, peripheral projection 34 the described releasing of the lid takes place without problems and with great facility and swiftness. The design of the edge flange of the lid brings about that the lid can be manufactured from a relatively hard plastic material, i.e. the same plastic material as the container, and that the edge flange of the lid can be arranged with such a relatively large pretension in relation to the edge portion of the container that the tightness of the lid in relation to the edge portion of the container is guaranteed. In figs. 7, 8, 9 and 10 there are shown modified embodiments of containers provided with lids in accordance with the invention. In the embodiment according to fig. 7 the edge portion 44 of the container is formed by a folded portion of the upper edge of the container, the downwardly facing edge surface 46 forming the engagement surface for the projection on the edge flange of the lid. The edge portion 44 is connected with the radially inwardly positioned portionof the wall of the container by means of a number of radially extending ribs 48. The embodiment according to fig. 7 has the same function as the embodiment according to figs. 1 - 6. Also in the embodiment according to figs. 8 and 9 the edge portion of the container is formed by folded portions of the upper edge of the container and the edge portion of the lid is designed with regard to the design of the edge portion of the container. Also the embodiments according to figs. 8 and 9 have the same function as the embodiment according to figs. 1 - 6. In the embodiment according to fig. 10 the lid is designed in substantially the same way as in the embodiment according to figs. 1 - 6. Thus, the lid has an edge portion 50 forming a downwardly open continuous channel 52 defined by an inner wall 54, an upper wall 56 and an outer wall which forms an edge flange 58. The wall 56 has at its inner surface a centrally positioned downwardly directed continuous bead 60 forming together with the inner wall 54 a channel 62. The edge flange 58 of the lid has at its lower free edge 33 a continuous inwardly directed projection 64. Between the projection 64 and the portion of the edge flange 58 positioned above the projection there is formed an outer, peripheral groove 66 forming a hinge allowing a restricted pivotal movement of the lower portion of the edge flange 58 on which the projection 64 is arranged. In the embodiment shown in fig. 10 the edge portion of the container is constituted by an upper sealing edge 68 and a radially projecting flange 70 positioned at some distance beneath the sealing edge and immediately beneath the peripheral bead 60 of the lid, the flange 70 having a downwardly extending skirt 72. The downwardly extending skirt 72 forms a downwardly facing engagement surface 74. The sealing edge 68 of the container sealingly engages the channel 62 of the lid while the inwardly directed projection 64 on the edge flange 58 of the lid engages beneath the downwardly extending skirt 72 of the flange 70 and, thus, is in engagement with the downwardly facing engagement surface 74 of the skirt 72. The embodiment according to fig. 10 have the same function as the embodiments according to figs. 1 - 9. Like in the embodiment according to fig. 10 the lid of the embodiment according to figs. 11 and 12 has an edge portion 76 forming a downwardly open, continuous channel 78 defined by an inner wall 80, an upper wall 82 and an outer wall which forms an edge flange 84. The upper wall 82 has at its inner surface a centrally positioned, downwardly directed, continuous bead 86 forming together with the inner wall 80 a channel 88. The edge flange 84 of the lid has an upper portion 90 with a smaller diameter and a lower portion 92 of a larger diameter, the portions being connected with each other by means of a conical shoulder 94. The free edge 96 of the edge flange portion 92 has a continuous, inwardly directed projection 98. Above the projection 98 the edge flange portion 92 has an inner, continuous groove 100, forming a hinge which allows a restricted pivotal movement of the edge flange portion 92 on which the projection 98 is positioned. A number of strengthening ribs 102 are positioned between the edge flange portion 90 and the centrally positioned, downwardly projecting, continuous bead 86. In the embodiment shown in figs. 11 and 12 the edge portion of the container is constituted by an upper sealing edge 104 and a skirt 106 positioned at a distance beneath the edge 104 and projecting downwardly-outwardly. The skirt 106 has an outwardly directed, continuous projection 108 forming a downwardly facing engagement surface 110. The sealing edge 104 of the container sealingly engages the channel 88 of the lid while the continuous, inwardly directed projection 98 on the edge flange portion 92 engages beneath the projection 108 on the skirt 106 and thus is in engagement with the downwardly facing engagement surface 110. In order to prevent such an inadvertant pressure on the edge flange portion 92 that might leed to an inadvertant removal of the lid from the container the container according to the embodiment shown in figs. 11 and 12 is provided with a radially projecting protective flange 112. The protective flange 112 is formed by the free edge portion of the skirt 106 of the edge portion of the container and projects so far that the outer edge thereof is positioned radially outside the portion 92 of the lid edge flange 84. In order to make it possible to grasp the portion 92 when the lid shall advertantly be teared off from the container the protective flange 112 is at at least one section of its periphery provided with a recess 114. The invention can be modified within the scope of the following claims.

Claims: A container with a lid consisting of plastic material, the edge portion (12) of the lid (4) having a peripheral, downwardly directed edge flange (28) which encloses an edge portion (10) positioned at the opening of the container and at its surface facing this edge portion has an inwardly directed, continuous projection (34) which for releasably retaining the lid to the container engages beneath a downwardly facing engagement surface (20) on the edge portion of the container, the lid (4) having immediately above the inwardly directed, continuous projection (34) a hinge (36) formed by means of material reduction and having the lower free edge surface (33) of the edge flange positioned immediately beneath the inwardly directed, continuous projection (34), characterized in that the peripheral, downwardly directed edge flange (28) of the lid (4) is along at least one section of its periphery provided with strengthening means (38). A container with a lid according to claim 1, characterized in that the strengthening means are constituted by radially extending ribs (38) extending across the hinge for forming a gripping portion. A container with a lid according to claim 1 or 2, characterized in that the edge flange of the lid forms an outer wall (28) of a downwardly open, continuous channel (22) sealingly receiving the edge portion (10) positioned at the opening of the container. A container with a lid according to claim 3, characterized in that the wall (28) is above the hinge formed by the material reduction (36) provided with strengthening means (40), for example in the form of radially extending ribs. A container with a lid according to any of the preceding claims, characterized in that the edge portion of the container is formed by an upwardly directed wall portion having a free upper edge surface (14) and a radially outwardly extending bead (16) which at its outer edge forms the downwardly facing engagement surface (20) of the edge portion (10) of the container (12). A container with a lid according to claims 4 and 5, characterized in that the downwardly open continuous channel (22) of the lid has at its bottom a peripheral projection (30) which is connected with the edge flange (28) of the lid by means of a number of radially extending ribs (40) distributed along the periphery of the lid and that the ribs at the opposite edge from the edge flange of the lid together with the opposite wall (24) of the downwardly open continuous channel of the lid forms an annular space (32) for receiving the edge portion of the container formed as an upwardly directed wall portion thereof. A container with a lid according to any of the preceding claims, characterized in that the downwardly facing engagement surface of the edge portion of the container is constituted by an outwardly-downwardly folded edge portion (44) of the container. A container with a lid according to claim 7, characterized in that the folded edge portion is connected with the radially inside positioned portion of the wall of the container by means of a number of radially extending ribs (48). A container with a lid according to any of the preceding claims, characterized in that the container has immediately beneath the lower, free edge surface of the lid edge flange (84) a radially projecting protective flange (112) for preventing that the lid is inadvertantly released from the container. A container with a lid according to claim 9, characterized in that the protective flange (112) is constituted by a free edge portion of a skirt (106) projecting downwardly-outwardly from the edge portion of the container, the skirt (106) having an outwardly directed projection (108) forming at its lower surface a downwardly facing engagement surface (110) of the container.

Inventors: ANDERSSON INGE, JOENSSON SVEN-AKE, ANDERSSON, INGE, JOENSSON, SVEN-AKE, Jönsson, Sven-Ake
Applicants: LAGAN PLAST AB
Application year: 1992
Main classification: B65D43
IPC codes: B65D43