WO2005117523A2

WO2005117523A2 - Device and method for clamping and sealing containers

Info

Publication number: WO2005117523A2
Application number: PCT/IL2005/000579
Authority: WO
Inventors: Levin Shalom
Original assignee: Concept & Design Ltd.
Priority date: 2004-06-02
Filing date: 2005-06-02
Publication date: 2005-12-15
Also published as: WO2005117523A3

Abstract

A snugly-fitting C-clamp strip device evenly and tightly clamping and sealing a container to a matching cover, the container and cover comprising a single locker unit designed for tool-free attachment and removal of cover and container. The clamp is formed as a continuous strip of ribs being joined in alternating upper and lower contiguous ends by shaped links. Both the container and matching cover have protruding lip elements formed as a flange around their respective perimeters which provide a hold for the clamping device. The edges of the lip elements are thus clamped and sealed tightly together under a uniform pressure applied along the common contact perimeter, thus alleviating the need for fasteners.

Description

DEVICE AND METHOD FOR CLAMPING AND SEALING CONTAINERS

FIELD OF THE INVENTION The present invention relates generally to a device and method for clamping and sealing containers, and more specifically, to a C-clamp strip for evenly and tightly clamping and sealing a locker unit comprising a container having a matching cover.

BACKGROUND OF THE INVENTION Current practices for clamping and sealing covers onto containers usually involve using a few fasteners evenly spaced around the perimeter of a container for seal-tight clamping, but this generally is insufficient, especially where a watertight or gastight seal is required. There is an uneven pressure along the seal due to the spacing between the fasteners and, because of this, even a gasket or rubber flange may not be sufficient to fully seal such containers. Additional measures to be applied to such containers to solve the problem of an even, tight seal involve costly increases in the direct cost of the method per unit container due to the fact that a more rigid construction of a container and its cover is very problematic, especially for plastic containers and covers. Furthermore, efforts to produce an evenly clamped and sealed container and matching cover may also involve more handling and allocation of time, which is also an overhead expense. In aluminum or plastic boxes, special inserts made of brass or stainless steel are needed to implement rigid tightening with fasteners, such as screws. In cases when a peripheral seal is utilized between the opposing faces of the container and its matching cover, tightening fasteners, such as a few screws around the perimeter joining the cover to the container, produces an uneven pressure and there is a high possibility of leakage about the mid-space between fasteners.

SUMMARY OF THE INVENTION Accordingly, it is a broad object of the present invention to overcome the problems of the prior art and to provide a C-clamp strip device for evenly and tightly clamping and sealing a container having a matching cover. Therefore there is provided a clamping device comprising a plurality of springlike ribs having a C-shaped profile, the plurality being joined at alternating ends by a shaped link formed inverted to the orientation of the C-shape of the ribs. The clamping device of the present invention, in a preferred embodiment thereof, is a spring-like C-clamp, seen in a cross-section view of an extruded profile, which fits snugly around a flange formed along the common contact perimeter between a container and its matching cover; the container and cover comprising a locker unit. In general, the clamping device comprises at least one pair of spring-like ribs, but in a preferred embodiment of the invention, is formed as a continuous strip of ribs being joined in alternating upper and lower contiguous ends by shaped links. Both the container and matching cover have protruding lip elements formed around their respective perimeters, which provide a hold for the clamping device. The edges of the lip elements are thus clamped and sealed tightly together with a uniform pressure along the common contact perimeter. In the method of the invention, there is no need for bolts or screws for additional clamping of the cover to the container, or for tighter sealing, as the clamping device, in the form of a strip, replaces such fasteners. In a preferred embodiment of the invention, the clamping device, hereinafter referred to as a clamping strip, provides uniform pressure for sealing containers in most, if not all, applications. For example, a 15x15 square container is provided with a 600 kg. clamping force. In a preferred embodiment of the invention, the clamping strip is designed to provide 2 kg. /cm. pressure of the strip, although other embodiments allow for 10 kg. /cm. pressure or more. In a preferred embodiment of the present invention, the clamping strip is made of semi-rigid plastic, but other spring-like materials, such as, spring steel, beryllium copper, and the like are also usable. Furthermore, the clamping strip is provided, in one embodiment thereof, in an overlay of some decorative material, such as PVC on stainless steel, as is known to those skilled in the art. The clamping strip is provided, in an alternative embodiment thereof, in a solid form for straight-line application with a higher clamping force. Alternatively, the clamping strip is provided in a slotted embodiment for application on containers having shaped contours where a straight clamping strip would not be suitable. The slotted clamping strip allows for bending around the corners of a container for improved clamping and sealing. In all embodiments of the invention, the clamping strip is conveniently designed for tool-free installation and removal. Additional features and advantages of the invention will become apparent from the following drawings and description.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention with regard to the embodiments thereof, reference is made to the accompanying drawings, not to scale, in which like numerals designate corresponding sections or elements throughout, and in which: Fig. 1A is a perspective view of a section of a continuously formed C-shaped slotted clamping strip constructed in accordance with the principles of the invention; Fig. IB is a perspective view of a solid, C-shaped profile clamping strip; Fig. 2 is an exploded perspective view of a container and matching cover fitted with a few clamping strips in accordance with the principles of the invention; Fig. 3 is a perspective view of the container of Fig. 2 shown in a closed condition with a detail cut-away revealing the clamping strip; Fig. 4 is an enlarged detail view A of the clamping strip of Fig. 3; Fig. 5 is an exploded perspective view of another embodiment of the method of clamping and sealing a container with a closed ring in accordance with the principles of the invention; Fig. 6 is an exploded perspective view of still another embodiment of the method of clamping and sealing a container in accordance with the principles of the invention; Fig. 7 is an exploded perspective view of yet another embodiment of the method of clamping and sealing a container in accordance with the principles of the invention; and Figs. 8A-8D are detailed, cross-sectional views of alternative embodiments of the method of closing, sealing, and clamping various containers utilizing the clamping strip of the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to Fig. 1A, there is shown a perspective view of a preferred embodiment of a section of a continuously formed C-shaped clamping strip 10 constructed in accordance with the principles of the invention. The C-shaped profile of clamping strip 10 provides a unifoπΗ gripping force around the perimeter of a locker unit (see detail A, Fig. 3), comprising a container and a matching, fitted cover, when clamping strip 10 is mounted on the protruding lips of the container and cover, which are aligned and fitted together when the container is closed. Clamping strip 10 is formed from a plurality of non-parallel ribs 12 which are connected by a plurality of shaped links 14 at alternating upper and lower points where the non-parallel ribs 12 are in closest juncture. A single, slotted strip is unable to be bent around the corners of a container and therefore a single strip is unusable to close the container. In another embodiment of the invention, the ribs are parallel to one another along the length of the C-shaped profile. Shaped links 14 are constructed in a profile having a curved surface oriented in parallel to the longitudinal axis of clamping strip 10 which, when applied to a closed locker unit (see Fig. 8A), permits attachment to the perimeter of the respective lower 32 and upper lips 26 of a container and its matching cover, and locks clamping strip 10 onto the locker unit (see Fig. 8A). Clamping strip 10 may be constructed from any suitable material, but in a preferred embodiment of the invention, is made of spring steel. Fig. IB is a perspective view of a continuously solid clamping strip without any slots as in the clamping strip of Fig. 1A. This solid clamping strip 10 has much higher tightening force than the slotted embodiment, but can its application is limited to implementations where the container locking unit is provided with straight edges or only lightly curved edges. Fig. 2 is an exploded perspective view of a locker unit provided with a solid clamping strip 36 in accordance with the principles of the invention. Referring to Fig. 2, there is shown a locker unit 22 comprising a container cover 24 having a perimeter cover lip element 26 which is provided with a matching sealing gasket 28 disposed so as to at least partially fit within the groove 30 formed within a container lip element 32 of a container 34. Cover lip element 26 exactly matches the contours of container lip element 32 of container 34 and fully seals gasket 28 between cover lip element 26 and container lip element 32 within groove 30 when locker unit 22 is fully assembled and sealed with a clamping strip, such as shown in Fig. IB. In Fig. 2, the solid clamping spring, covered with a decorative elastic plastic or rubber material, comprises longitudinal elements 36, side elements 38, and corner elements 40, which, when assembled, completely encompass, seal, and lock cover 24 to container 34 along the perimeter of locker unit 22 formed by their respective lip elements 26, 32. Fig. 3 is a perspective view of the assembled and closed locker unit of Fig. 2 shown with a detail of the decorative cover in a cut-away view A, indicated by circular arrows. Cut-away view A reveals a small section of clamping strip 10 as shown in Fig. 1 which encompasses the full perimeter of locker unit 22 at the contact edges of cover 24 and container 34, effectively and efficiently sealing locker unit 22. Fig. 4 is an enlarged, cut-away view A from Fig. 3 showing details of the clamping strip which is not visible, being integral with longitudinal elements 36, side elements 38, and corner elements 40 which completely surround and form the boundary of the perimeter of locker 22. Ribs 12 and links 14 are formed in a continuous pattern along the clamping strip. In the embodiment of the invention shown in Figs. 3 and 4, the clamping strip is embedded within a protective, decorative material which is made of resilient plastic. Other materials, suitably formed, may be used as well. Notice that the ribs 12 and links 14 maintain pressure on the lip elements 26, 32 of the cover and container, respectively, to ensure a tight seal. Fig. 5 is an exploded perspective view of another embodiment of the invention for sealing a container with a closed ring. The locker unit 42 shown in Fig. 5 is assembled as described heretofore in respect to Fig. 2, but an optional locking form 46 in the shape of a closed ring and retaining fastener 48, such as, for example, a locking bolt, are employed when locker unit 42 requires greater security and a reinforced seal. When a clamping strip, including a protective, decorative cover 44, is mounted onto locker 42, there is an adjusting gap 50, which permits easier assembly. Locking form 46 serves to cover and tightly clamp and seal this almost unnoticeable gap 50 between sectional elements (see Figs. 2 and 3) comprising the clamping strip 44 fitted along the perimeter of locker unit 42. Fig. 6 is an exploded perspective view of still another embodiment of the method of clamping and sealing a locker unit in accordance with the principles of the invention. Locker unit 52 is constructed in an irregular trapezoidal form and comprises a cover 54, a sealing gasket 56, a clamping strip 58 (enclosed in a decorative cover as hereinbefore described), and a container 60 which are assembled as indicated and as hereinbefore described in reference to locker units 22 and 42. It should be noted that the specific shape of the various embodiments of the locker units can vary as much as can their size or capacity without substantially detracting from the principles of the invention. The embodiments of the invention shown are only by way of example and not to scale. Fig. 7 is an exploded perspective view of yet another embodiment of the invention for clamping and sealing a container. Locker unit 62 is similar to that of Fig. 6, but with cover 64 and container 66 sealed utilizing only closed loop clamping strip 58 (integral to a decorative, protective material) without the use of a gasket as in the aforementioned embodiments of the invention. Container lip element 68 is flat and not grooved and therefore provides maximum contact area against the matching lip element 70 of cover 64. The lip elements 68, 70 may be sealed with an adhesive, or a planar gasket, as is known to those skilled in the art, and the application of clamping strip 58 provides sufficient pressure to effectively and efficiently clamp and seal the locker unit 62 without a gasket and hence at a unit cost savings. The embodiments of the invention shown in Figs. 2, 5, and 6 are more suitable for gas-tight and water-tight seals, where it is recommended that a gasket be included, but for ordinary use, the clamping strip of the invention is eminently suitable for clamping and sealing most containers at an economical cost. Figs. 8A-8D are detailed, enlarged, cross-sectional views of alternative embodiments of the method of closing, sealing, and clamping various containers utilizing the clamping strip of the invention. Referring now to Fig. 8A there is shown an enlarged, cross-section of a cover lip element 26 pressed against a container lip element 32 so as to cause a radial squeeze of an oversize gasket 28 lying within a narrow groove space defined by the lip elements. The most popular design for sealing a container with its cover is by using an ordinary O-ring gasket lying in a slot formed in the cover or in a lip of the side of the container and axially forced against a flat surface of the corresponding lip in the cover. Axial force is effected by the tightening force, spacing of fasteners, such as bolts, and the rigidity of the cover. In the embodiment of the invention shown in Figs. 8A/B/C, the gasket is formed in a figure-eight section profile, and from the very moment that the gasket is set into the slot formed along the perimeter of the lip of the container and the container is covered with its matching cover, the meeting of the corresponding lips 26, 32 of a typical locker unit form a tight seal which is achieved by the radial squeezing action of gasket 28 and not, as in the prior art, by the axial tightening force produced either by bolts or a C-spring. In Fig. 8A, the pressure against the lips of elements 26, 32 is provided by clamping strip 10 which is embedded in a protective material 72 and provided with a decorative coating 44. In Fig. 8B, the protective material 72 enclosing clamping strip 10 is covered with a metallic locking form 46 as in Fig. 5. In Fig. 8C, the effect of the pressure from clamping strip 10 is evident in the distortion of gasket 56 which makes a high-level seal between lip elements 26 and 32 such that a locker unit fitted in this manner is adaptable for gastight or watertight applications. In Fig. 8D, the cross-section view represents locker unit 62 from Fig. 7 wherein the respective lip elements 68, 70 of container 66 and cover 64 are in maximum surface contact under pressure from a very simple clamping strip 58, without the use of a gasket. Having described the invention with regard to certain specific embodiments thereof, it is to be understood that the description is not meant as a limitation, since further modifications may now suggest themselves to those skilled in the art, and it is intended to cover such modifications as fall within the scope of the appended claims.

Claims

CLAIMS:

1. A clamping device comprising a plurality of spring-like ribs having a C-shaped profile, said plurality being joined at alternating ends by a shaped link formed inverted to the orientation of said C-shaped profile of said ribs.

2. The clamping device of claim 1 wherein said plurality of spring-like ribs comprises a solid C-spring without any slots.

3. The clamping device of claim 1 wherein said C-shaped profile is adapted for gripping matching lip elements formed around the open edges of the respective perimeters of a cover and a matching container.

4. The clamping device of claim 3 wherein said cover and said matching container comprise a locker unit.

5. The clamping device of claim 4 wherein said locker unit, when fitted with said clamping device, enables said lip elements to make physical contact such that said locker unit is in a closed, clamped, and sealed condition.

6. The clamping device of claim 3 wherein said lip elements are provided with a groove adapted to accommodate a sealing gasket.

7. The clamping device of claim 6 wherein said sealing gasket is formed in a figure-eight profile.

8. The clamping device of claim 6 wherein said sealing gasket is disposed in matching slots of both a cover and a container so as to clamp and seal the locker unit by being radially squeezed therebetween.

9. The clamping device of claim 1 wherein said plurality of spring-like ribs having said shaped link are enclosed in a cover characterized as having at least one of the features: protective and decorative.

10. The clamping device of claim 1 wherein said clamping strip is made of a spring-like material selected from at least one of the following types: semi-rigid plastic, spring steel, and beryllium copper.

1 1. The clamping device of claim 1 wherein said C-spring is made of electrically conductive materials so as to provide electrical conductivity between a container and a matching cover comprising a locker unit for shielding and grounding electronic components stored in said locker unit when sealed with said clamping device.

12. A method for sealing a container comprising: providing a clamping device comprising a plurality of spring-like ribs having a C-shaped profile, said plurality being joined at alternating ends by a shaped link formed inverted to the orientation of said C-shaped profile of said ribs; mounting said clamping device around the common perimeter between a container and matching cover along a flange formed around their common perimeter, wherein when said clamping device is applied to said container and matching cover, siad locking unit is tightly sealed and free of the need for fasteners.