Claims:We claim
1. A tamper evident locking system for container – lid attachments and its locking comprising:
a lid having one or more outwardly extending downward protruding lockable member, each including a first lock segment facing outwards adapted to interlock with a cooperative container outer wall inner face and a second lock segment facing inwards adapted to cooperate with a cooperative container inner wall outer face of the container with said container outer wall inner face and said container inner wall outer face defining a space for securely locking said protruding lockable member of said lid with respect to said container in locked condition;
said protruding lockable member portion in locked space between said container outer wall inner face and said container inner wall outer face maintained in deformation free stable locked condition involving selectively disposed support ribs and pusher extending from said container’s side wall outer face in said space to lock any unlocking movement with respect to the said first and second lock segments of the protruding lockable member and said container faces and/or its cooperative interlocking members with said fist and second lock segments;
a peripheral tear member connecting lid top and its said protruding lockable member enabling tamper evident tear to open the lid top for unlocking detached from said atleast the portion of said protruding lockable member extending into said space for locking with the container maintained irreversibly locked with respect to the container as proof of container opening.

2. The tamper evident locking system for container – lid attachments and its locking as claimed in claim 1, wherein said first lock segment comprises an externally protruding wedge shaped lock which cooperates with a counter acting and blocking shaped internal stop in said container outer wall inner face and adapted to work as a lid arresting arrangement and said second lock segment facing inwards and extending beyond said first lock segment and disposed close to end region of free end portion of the downwardly protruding lock member is having a wedge shaped lock which is arrested under locked condition with respect to the supporting rib and the pusher enabling anti delidding lock along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking.

3. The tamper evident locking system for container – lid attachments and its locking as claimed in claim 1, wherein the space for securely locking the protruding lockable member between said container outer wall inner face and said container inner wall outer face maintained comprises one or more peripheral slots, each said peripheral slot is configured to engage with at least one of the protruding lockable member with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container.

4. The tamper evident locking system for container – lid attachments and its locking as claimed in claims 1 to 3, wherein the peripheral slot on the container comprises
a ring extending continuously around the sidewall of the container and proximal to open top of the container, said ring forming the container outer wall inner face and said sidewall facing the ring forms the container inner wall outer face;
plurality of radial connecting members for extremely spaced apart mounting of said ring on the sidewall, whereby any two consecutive connecting members in combination with the ring and the sidewall portion defines one of the peripheral slots.

5. The tamper evident locking system for container – lid attachments and its locking as claimed in claims 1 to 4, wherein the wedge shaped lock of the first lock segment is integrally moulded on the outer side of the protruding lockable member and comprises a forward inclined slope.

6. The tamper evident locking system for container – lid attachments and its locking as claimed in claims 1 to 5, wherein the wedge shaped lock of the second lock segment is integrally moulded on the inner side of the protruding lockable member and comprises a forward inclined slope.

7. The tamper evident locking system for container – lid attachments and its locking as claimed in claims 1 to 6, wherein the counter acting and blocking shaped internal stop includes backward inclined slope on the ring.

8. The tamper evident locking system for container – lid attachments and its locking as claimed in claims 1 to 7, wherein the pusher is configured to resiliently bias the protruding lockable member towards the outer side enabling the forward inclined to rides over the backward inclined slope on the ring and simultaneously the forward inclined lug to rides over the pusher element with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container.

9. The locking system as claimed in claims 1 to 8, wherein the forward inclined wedge shaped lock of the first lock segment is locked under the backward inclined slope on the ring and simultaneously the forward inclined wedge shaped lock of the second lock segment is locked under the pusher when lid is press fitted on the container ensuring locking of the lid with the container and thereby preventing any folding of the pusher and avoids detachment of the lid from the container even in bottom up orientation of the container or drop down condition of the container.

10. The locking system as claimed in claims 1 to 9, wherein the tear member is defined by score lines or discrete frangible bridges or ribs which connect the lid protrusions with the periphery of the lid.
, Description:FIELD OF THE INVENTION
This invention relates to secured lidding of a leak-proof pail or container. More specifically the present invention is directed to tamper evident locking system for a pail or container and lid thereof which can prevent detachment of the lid from the container specifically loaded container by enabling anti delidding lock between the container and the lid thereof along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking.

BACKGROUND OF THE INVENTION
Combinations Molded plastic container and press fitted lid thereof are extremely popular for use in shipping, storing and marketing a variety of products ranging from lubricants and paints to food products, at both individual consumer and bulk quantities. It is known to provide container-lid with their mutual locking combinations and tamper-evident characteristics through one or more of an assortment of locking structures including those which are partially or fully disabled by way of tear strips or tear bands.

The typical tear band is in provided in the lid with atleast one locking structure and a tear line which allows a portion of the outside peripheral skirt of the lid to be manually torn away fully or partially remove or disable the locking structure. The removal of the tear band provides a visual evidence that the lid has been manipulated for removal purposes. After the removal of the tear band, the lid may be completely detached from the container and either discarded or reused.

Various lid and containers or pails combination have been described in the prior art. Some of them are presented below as examples.

US7475788 discloses a molded plastic container and closure combination where the closure has removable tear band. This invention provides a closure which is readily manually altered by the removal of a tear band for opening but provides for easy and secure closing and reopening after removal of the tear band. Further features include a structure which enhances the stackability by transferring stacking loads through the closure structure to the container sidewall.

US7090088 discloses a combination of a molded plastic bucket and a tamper-evident closure with a zig-zag tear strip which permits the removal of a portion of the lowermost closure flange. The wedging and locking functions associated with the design of the edge or skirt of the closure provide an improved and more permanent seal of the closure to the bucket. Such a feature provides multiple buckets each of which is closed by a closure that enables easy stacking.

US8342354 discloses a molded plastic container with a "snap-ring" which acts as a transition structure between the container and the closure. An inverted u-shaped slot in the snap rig fits to the top edge of the container to transfer vertical stacking loads from the closure or ring to the container sidewall.

US6845877 discloses a plastic container with a snap closure and a snap element. The invention fulfills the special demands imposed on leak-profaneness, while simultaneously providing high load-bearing capacity.

US7740149 discloses apparatus and methods related to containers having a sidewall portion with vertical corrugation therein. The containers can be of a variety of shapes, sizes, cross- sections, and materials. The corrugation improves the container sidewall strength and resistance to buckling under compressive loads such as stacking of multiple containers.

US3567016 discloses a new and improved sealed container assembly with sealing connection between the closure and the open end of the container. The sealing consists of a multiple number of associated parts which reinforce each other and provide a high degree of stiffness at the open end of the container sufficient to withstand the usual rough handling to which shipping containers are subjected.

CA2676410 discloses container with axially extending, circumferential distributed ribs stack inside of the container wall. The stacking ribs serve to allow the stacking of several containers into each other. Each upper container can be supported in the respective lower container, such that the two cone-shaped vessel walls do not get jammed together.

US8256640 discloses container including one or more sidewalls that surround an internal cavity and wherein one or more of the sidewalls include a reinforcing web of increased wall thickness for having improved strength-to-material and/or strength-to-weight ratios.

Such prior art constructions work well. However, a lid construction with special features that enable easy handling, access while providing better tamper-evidence and locking functionality has not been known.

In a co-pending patent application 4705/CHE/2014, the applicant had disclosed a tamper-evident lid-container combination having specially designed tamper-evidence and a tear away band which can be pulled out in anti-clockwise direction around the periphery of the container. The lid has primary and secondary locking facilities which allow the container to be used effectively. The container is shaped and configured such that the lid fits into the sections defined so that a primary zone or zones of weight transfer between the closure and the container occurs at the surface of the side wall of the container. The lid is shaped and configured to get locked with container under the bias of a resilient container portion when the lid press fitted on the container. However such resilient container portion biased locking of the lid on the container does not effectively avoid the detachment of the lid from the container specifically loaded container in bottom up orientation of the loaded container or drop down condition of the loaded container.

Thus there has been a need for developing an improvement in locking between a container and its lid which can prevent detachment of the lid from the container specifically loaded container even in bottom up orientation of the loaded container or drop down condition of the loaded container.

OBJECT OF THE INVENTION
It is therefore the basic object of the invention to provide a container lid combination with new and improved lid – container locking which would ensure secured tamper evident lidding of the lid on the container in a leak-proof and tampare proof manner.

Another object of the invention is to provide a new and improved tamper evident lid – container locking system which would prevent detachment of the lid from the container specifically loaded container even in bottom up orientation of the loaded container or drop down condition of the loaded container.

Another object of the invention is to provide a new and improved tamper evident lid – container locking system which would enable anti delidding lock between the container and the lid thereof along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking.

Another object of the invention is to provide a lid with a tamper-evident feature and a tear band for capping on a container which would be adapted to get locked with the container and removable only breaking of the tamper-evident feature and a tear band.

SUMMARY OF THE INVENTION
Thus according to the basic aspect of the present invention there is provided a tamper evident locking system for container – lid attachments and its locking comprising:
a lid having one or more outwardly extending downward protruding lockable member, each including a first lock segment facing outwards adapted to interlock with a cooperative container outer wall inner face and a second lock segment facing inwards adapted to cooperate with a cooperative container inner wall outer face of the container with said container outer wall inner face and said container inner wall outer face defining a space for securely locking said protruding lockable member of said lid with respect to said container in locked condition;
said protruding lockable member portion in locked space between said container outer wall inner face and said container inner wall outer face maintained in deformation free stable locked condition involving selectively disposed support ribs and pusher extending from said container’s side wall outer face in said space to lock any unlocking movement with respect to the said first and second lock segments of the protruding lockable member and said container faces and/or its cooperative interlocking members with said fist and second lock segments;
a peripheral tear member connecting lid top and its said protruding lockable member enabling tamper evident tear to open the lid top for unlocking detached from said atleast the portion of said protruding lockable member extending into said space for locking with the container maintained irreversibly locked with respect to the container as proof of container opening.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, said first lock segment comprises an externally protruding wedge shaped lock which cooperates with a counter acting and blocking shaped internal stop in said container outer wall inner face and adapted to work as a lid arresting arrangement and said second lock segment facing inwards and extending beyond said first lock segment and disposed close to end region of free end portion of the downwardly protruding lock member is having a wedge shaped lock which is arrested under locked condition with respect to the supporting rib and the pusher enabling anti delidding lock along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the space for securely locking the protruding lockable member between said container outer wall inner face and said container inner wall outer face maintained comprises one or more peripheral slots, each said peripheral slot is configured to engage with at least one of the protruding lockable member with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the peripheral slot on the container comprises
a ring extending continuously around the sidewall of the container and proximal to open top of the container, said ring forming the container outer wall inner face and said sidewall facing the ring forms the container inner wall outer face;
plurality of radial connecting members for extremely spaced apart mounting of said ring on the sidewall, whereby any two consecutive connecting members in combination with the ring and the sidewall portion defines one of the peripheral slots.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the wedge shaped lock of the first lock segment is integrally moulded on the outer side of the protruding lockable member and comprises a forward inclined slope.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the wedge shaped lock of the second lock segment is integrally moulded on the inner side of the protruding lockable member and comprises a forward inclined slope.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the counter acting and blocking shaped internal stop includes backward inclined slope on the ring.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the pusher is configured to resiliently bias the protruding lockable member towards the outer side enabling the forward inclined to rides over the backward inclined slope on the ring and simultaneously the forward inclined lug to rides over the pusher element with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the forward inclined wedge shaped lock of the first lock segment is locked under the backward inclined slope on the ring and simultaneously the forward inclined wedge shaped lock of the second lock segment is locked under the pusher when lid is press fitted on the container ensuring locking of the lid with the container and thereby preventing any folding of the pusher and avoids detachment of the lid from the container even in bottom up orientation of the container or drop down condition of the container.

In a preferred embodiment of the present tamper evident locking system for container – lid attachments and its locking, the tear member is defined by score lines or discrete frangible bridges or ribs which connect the lid protrusions with the periphery of the lid.

BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A- 1D show the locking arrangements between a container and its lid in a typical container -lid combination.

FIG. 2A shows the locking arrangements between a container and its lid in accordance to an embodiment of the present invention.

FIG. 2B shows stage wise operation of the locking arrangements between a container and its lid in accordance to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS:

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the embodiment of the present invention, and together with the description serve to explain the principles of the invention.

As stated herein before, the present invention provides a tamper evident locking system for a pail or container and lid thereof which can prevent detachment of the lid from the container specifically loaded container even in bottom up orientation of the loaded container or drop down condition of the loaded container by enabling anti delidding lock between the container and the lid thereof along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking. The tamper evident locking system of the present invention is applicable to any pail/container – lid combination. On this reference is first invited from the accompanying fig 1A to fig 1D show the locking arrangements between a container and its lid in a typical container -lid combination.

As shown in the Fig 1A, lid-container locking arrangements in a typical container -lid combination include lid protrusions 2 on the lid periphery which are adapted to lockingly engage with the container or portions thereof. Specifically, the lid protrusions are lockingly engaged with the container or portions thereof with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container, as shown in the accompanying fig. 1B.

The lid-container locking configuration of fig. 1B is further illustrated in the accompanying fig. 1C. As shown in the referred fig 1C, the lid is fully secured on the container top. In this configuration, the lid protrusions 2 are locked in the container's peripheral slot 5, as forward inclined hump 3 on front of the lid protrusion 2 rides over backward inclined slope 4 on the engaging peripheral slot 5 and thereafter locked under the backward inclined slope 4 under resilient bias of a pusher element 1 of the container on the lid protrusions 2. Thus, in the typical container -lid combination, the lid is basically locked onto the container under the resilient bias of the pusher element 1 on the lid protrusions 2 which is not effective in preventing detachment of the lid from the container particularly in bottom up orientation of the loaded container or drop down condition of the loaded container.

This situation is further illustrated in the accompanying fig 1D. In bottom up orientation of the loaded container or drop down condition of the loaded container, the load of the container exerts a high radially outward force on the container sidewall which either folds the pusher element 1 beyond its resilient limit or reversely folds the pusher element 1, as shown in the referred illustrations respectively. In any of the folding, the pusher element 1 can not provide the resilient bias on the lid protrusions 2 resulting detachment of the lid from the container.

To avoid such detachment of the lid from the container particularly the loaded container, during the bottom up orientation of the loaded container or drop down condition of the loaded container, the present invention provides a tamper evident locking system for a pail or container and lid thereof. The tamper evident locking system of the present invention is illustrated in the accompanying Fig 2A.

As shown in the above referred fig 2, the present tamper evident locking system for container – lid attachment and lock includes one or more specifically designed outwardly extending downward protruding lockable member 2, one or more corresponding locking spaces 10 defined by a container outer wall inner face and a container inner wall outer face, whereby each of the locking spaces 10 can accommodates at least one of the protruding lockable member 2 for locking engagement thereto with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container. The protruding lockable member portion is securely maintained in the locked space between said container outer wall inner face and said container inner wall outer face for deformation free stable locked condition between the container and lid thereof.

In the present locking system, each of the protruding lockable member 2 comprises a first lock segment 3 on its outer side facing outwards and a second lock segment 6 on its inner side facing inwards. The first lock segment 3 is adapted to interlock with the cooperative container outer wall inner face and the second lock segment 6 is adapted to cooperate with the cooperative container inner wall outer face of the container.

The protruding lockable member portion being locked in the space between said container outer wall inner face and said container inner wall outer face maintains the deformation free stable locked condition involving selectively disposed support ribs 7 and pusher 1. The support ribs 7 and the pusher 1 are integral to sidewall of the container and extending from said container’s side wall outer face in said space 10 to lock any unlocking movement with respect to the said first and second lock segments of the protruding lockable member and said container faces and/or its cooperative interlocking members with said fist and second lock segments.

A peripheral tear member 9 is provided to connect lid top and its protruding lockable members 2 enabling tamper evident tear to open the lid top for unlocking detached from said atleast the portion of said protruding lockable member extending into said space for locking with the container maintained irreversibly locked with respect to the container as proof of container opening.

In a preferred embodiment of the present system, the first lock segment 3 comprises an externally protruding wedge shaped lock which cooperates with a counter acting and blocking shaped internal stop in said container outer wall inner face and adapted to work as a lid arresting arrangement, as shown in the fig 2A. The forward inclined wedge shaped lock of the first lock segment 3 is integrally moulded on the outer side of the protruding lockable member 2 and proximal to the free end portion of protruding lockable member 2 that facing the locking space 10 on the container.

The second lock segment 6 facing inwards and extending beyond said first lock segment is disposed close to end region of the free end portion of the downwardly protruding lock member 2. The second lock segment 6 is also comprises wedge shaped lock with forward inclined slope, as shown in the fig 2A. The forward inclined wedge shaped second lock segment 6 is integrally moulded on the inner side of the lid protrusion 2 and it is arrested under locked condition with respect to the supporting rib 7 and the pusher 1 such as to enable the anti delidding lock along with preventing any deformation during pack drop down or in case of pack upside down under load of content for a secured tamper evident locking.

In a preferred embodiment of the present locking system, the space for securely locking the protruding lockable member between said container outer wall inner face and said container inner wall outer face maintained comprises one or more peripheral slots. This peripheral slot 10 comprises a peripheral ring 11 which extends continuously around sidewall of the container and proximal to open top of the container. The peripheral ring 11 forms the container outer wall inner face and said sidewall facing the ring forms the container inner wall outer face. Multiple radially outward connecting members 8 are provided on the container sidewall for extremely mounting the peripheral ring 11 on the sidewall such as any two consecutive connecting members 8 in combination with the ring 11 and the sidewall defines one of the peripheral slots.

As shown in the fig 2A, the counter acting and blocking shaped internal stop on the peripheral slot 10 includes the backward inclined slope 4 on the ring portion.

In a preferred embodiment, the protruding lockable member 2 are integrally moulded across entire periphery of the lid through the tamper-evident breakable tear band 9. This tear band 9 is extends continuously around the lid periphery, whereby the tear band 9 is peeled along the lid periphery to completely lift the lid from the container while the protruding lockable member portion remains attached to the peripheral slot on the container. The the tear band may be defined by score lines or discrete frangible bridges or ribs which connect the lid protrusions with the periphery of the lid. The tear band cannot be replaced such that when the lid is reapplied to the container, the absence of the tear band provides a visual indication that the container has been opened. The tear band is opened by pulling a tab in a direction along the circumference of the container.

Reference is now invited from the accompanying fig 2B which shows the stage wise activation of the present locking system. As clearly illustrated in the fig 2B, the pusher element 1 is resiliently bias the protruding lockable member 2 towards the outer side [stage A and stage B]. Such outward resilient bias enables the forward inclined wedge structured first lock segment 3 to rides over the backward inclined slope 4 on the ring and simultaneously the forward inclined wedge structured second lock segment 6 to rides over the pusher element 1 with vertically downward motion of the lid with respect to the container during press fitting of the lid on the container [stage C]. Finally, the forward inclined wedge structured first lock segment 3 is locked under the backward inclined slope 4 on the ring 11 and simultaneously the forward inclined wedge structured second lock segment 6 is locked under the pusher element 1 when lid is press fitted on the container [stage D]. This dual locking prevents any folding of the pusher element 1 thus ensuring locking of the lid with the container and preventing detachment of the lid from the container even in bottom up orientation of the container or drop down condition of the container.

The aforementioned described features help alleviate the problems associated with prior art technologies. It will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.

It is to be understood, however, that the present invention would not be limited by any means to the parts, arrangements and materials that are not specifically described, and any change to the materials, variations, sizes and modifications can be made without departing from the spirits and scope described in the present invention.