Patent Application
20060042982
The invention relates generally to containers having end portions sealed to corresponding container bodies and, more particularly, to welding rod containers with metal ends.
Welding rods may be used in various types of welding including, for example, their use with conventional electric welders, sometimes referred to as stick welders, where welding may be performed by creating an electric arc between the end of a welding rod and the work piece or work pieces. Various other welding and bonding processes may utilize welding rods, such as processes that inject additional materials into a welding location for improving efficiency, lowering cost, removing/preventing impurities, etc. Welding rods may contain a flux or flux generating material covering a metal rod for preventing oxidation of the welding rod material and areas adjoining the work piece. The rods may contain other additives, depending on the particular welding application.
A welding operator may elect to use any of several different welding rod sizes and materials, depending on the job being performed, cost considerations, etc. For example, the operator may choose to weld thin material one minute and thick material the next, changing welding rods as to material or size as appropriate for welding different pieces. Such different size welding rods, that may be formed of different materials, are typically provided in separate containers.
It is often desirable to prevent welding rods from being exposed to water, air, and other impurities in order to prevent oxidation and lowering of welding efficiency and quality. Therefore, welding rods are typically provided in sealed containers that can include, for example, a cover for re-sealing the container after it has been opened. However, conventional welding rod containers do not optimize a so-called “easy-open” structure, and do not optimize welding rod container safety to address concerns such as the possibility of an operator's hand being cut on a sharp exposed edge created when opening an easy-open welding rod container.
For example, the operator may position an opened welding rod container near a welder and then insert his hand into the opened container to retrieve a welding rod. In doing so, the operator may be wearing a welding shield and may have his attention directed to other matters, whereby he may inadvertently risk being cut by a sharp fractured score-line of a conventional easy-open container.
It is an object of the invention to provide an improved welding rod container overcoming some of the problems and shortcomings of the prior art, including those referred to above.
Another object of the invention is to provide an easy-open container allowing a cooperation of structural elements for optimizing an ease of opening the container.
Another object of the invention is to provide an easy-open welding rod container with a reduced risk of hand contact with a sharp edge when a user reaches into the opened container.
Still another object of the invention is to provide a pull-tab type easy-open container allowing a cooperation of structural elements for reducing the amount of sharp edge exposure created by opening the container.
Yet another object of the invention is to provide a simple welding rod container form that allows for easy manufacturing thereof.
How these and other objects are accomplished will become apparent from the following descriptions and the drawings.
According to an aspect of the invention, in a welding rod container of the type including (a) an elongate container body of rectangular cross-section and terminating at an open-end edge, (b) a metal end having a permanent portion with a rectangular outer edge secured to the open-end edge of the body and a removable portion defined by a tear-line, and (c) a pull-tab on the removable portion for manual fracture of the tear-line and removal of the removable portion to open the container, an improvement includes: the permanent portion of the metal end having a double-bend portion as an innermost blunt edge, the double-bend portion serving to recess the tear-line and removable portion, the tear-line being positioned such that it is away from hand contact when a user reaches into the opened container; and, the tear-line extending around the pull-tab and from there, on either side of the pull-tab, across the metal end in directions diverging from adjacent outer edges of the metal end, whereby such double-bend portion and tear-line cooperate for easy opening and edge safety.
According to another aspect of the invention, a welding rod container includes a rectangular body, and a unitary rectangular metal end having: a permanent portion secured at its outer edge to the body and having a flange terminating inwardly in a double-bend portion, the double-bend portion including an inwardly-extending lowermost level; and a removable portion having a peripheral edge joined to the lowermost level of the double-bend portion at a tear-line, the lowermost level and peripheral edge having first and second offset levels, the tear-line being formed by the offset juncture thereof.
According to a further aspect of the invention, a welding rod container includes a container body of a size at least as long as a welding rod to be contained therein, and a unitary rectangular metal end including: a permanent portion secured at its outer edge to the body and having an inwardly-extending flange; and, a removable portion having a peripheral edge joined to the inwardly-extending flange at a tear-line, where the inwardly-extending flange of the permanent portion and the peripheral edge of the removable portion have respective first and second offset thicknesses, the tear-line being formed by the offset juncture thereof.
As a result of the present invention, structural portions of a welding rod container combine in cooperative fashion to assist the ease of opening the container. In addition, safety is improved as a result of less exposure of potential sharp edges.
The foregoing summary does not limit the invention, which is instead defined by the attached claims.
FIG. is a perspective view of a welding rod container 10 according to an exemplary embodiment of the invention. Container 10 has an elongated main container portion 12 having a length greater than a length of welding rods to be held therein. Main container portion 12 may be formed of any suitable durable, air-tight, water-tight material such as metal, resin, and others. Main container portion 12 preferably has an even and level upper edge 13 that may include a flat, flanged, or other shaped surface, and that provides the perimeter of an open end thereof. Such upper edge 13 provides a location for attaching main container portion 12 to a metal end portion 14.
Metal end 14 has a permanent portion 22 and a temporary portion 23 enclosed by permanent portion 22 along a tear-line 41. The outer perimeter of permanent portion 22 has a horizontal flange 24. Flange 24, as discussed further below, may also be referred to as a “seaming panel.” A vertical portion 25 of metal end 14 is formed at the inner perimeter of the square formed by flange 24 as the result of a bend 26 of ninety degrees having a radial curvature. Vertical portion 25 extends to a lower radial bend 27 of ninety degrees that redirects sheet 21 of permanent portion 22 inwardly to form a middle portion 28 that is essentially in parallel with flange 24 and that provides the flat top surface of the permanent portion 22.
Middle portion 28 extends inwardly to a double-bend portion 61 that includes a first 180 degree bend 64, a second 180 degree bend 65, and a middle portion therebetween. After second bend 65, double-bend portion 61 extends inwardly as a permanent end portion 66 that terminates at tear-line 40. Tear-line 40 is formed by the offset relation of two levels 44, 45 of sheet 21, at a location where permanent end portion 66 joins temporary peripheral portion 67. Tear-line 40 is preferably located proximate the inner peripheral blunt edge 62 formed at the apex of first bend 61, as shown by example in
Tear-line 40 defines the juncture between temporary portion 23 and permanent portion 22. Tear-line 40 preferably forms such juncture as a diamond-shaped line when viewed from above as shown in the top plan illustration of
A moustache score 81 is formed in temporary portion 23 adjacent rivet 37 and perpendicular to lengthwise tab pulling axis 32. The pointed end portion 33 of pull-tab 31 may be positioned so as to abut both the adjacent double-bend portion 61 and tear-line 40. Metal sheet 21 in the area 82 of temporary portion 23 under pull-tab 31 may be formed as a raised portion 83 where rivet 37 does not extend inside main container portion 12.
A raised panel 90 is formed as an island type structure in temporary portion 23. Although shown as a raised panel, the panel 90 may alternatively be formed as a recessed panel. An embossed logo 85 or other indicia may be stamped, engraved, or otherwise formed on raised panel 90. Raised panel 90 has a side formed essentially perpendicular to lengthwise tab pulling axis 32. The remainder of the perimeter of raised panel 90 is formed to be essentially in parallel with the respective adjacent parts of tear-line 40. For example, side 91 of raised panel 90 is essentially in parallel with side 55 of tear-line 40, side 92 of raised panel 90 is essentially in parallel with side 56 of tear-line 40, and short intermediate sides 93, 94 of raised panel 90 are essentially in parallel with respective adjacent tear-line portions 57, 58.
Pull-tab 31 has a pointed end section 33 adapted for piercing tear-line 40 near corner 46 when tab 31 is pulled upwardly in a conventional manner. Pull-tab 31 has a middle section 34 secured to a slightly raised section 83 of temporary portion 23 with rivet 37 passing through hole 36 of middle section 34. Middle section 34 is at a slight angle with respect to pointed end section 33. A pulling portion 35 of pull-tab 31 is slightly angled with respect to middle section 34 and has a center opening 38 adapted for receiving a user's finger under a rounded part 39 of a lateral section 30.
A sealing compound 75 is used for assuring the watertight sealing between metal end portion 14 and main container portion 12. Vertical portion 25 may also be bonded to main container portion 12. Sealing compound 75 may be placed along the under side of flange/sealing panel 29, at the juncture of flange 29 and vertical portion 25, and/or along vertical portion 25. Then, the forming of a seam and/or other sealing type bonding between main portion 12 and end 14 is performed.
In various applications, a seal between the metal end 14 and the main container portion may also be made by use of an adhesive, heat, sonic heating, high-frequency heating, or by heating the main container portion 12 (if it is metal) using electrical induction or by local direct heat application.
In forming welding rod container 10, tear-line 40 may be created by a precise partial shearing or by a stamping operation that creates the boundary 58 between temporary and permanent portions, 23, 22, respectively. Such boundary 58 preferably has a vertical thickness from twenty to fifty percent of the nominal thickness 59 of metal sheet 21, depending on the particular material being used. An optimum thickness of the boundary 58 should be large enough to prevent the possibility of unwanted tearing and small enough to allow easy tearing when pull-tab 31 is pulled.
A welding technician may open welding rod container 10 by holding the container 12 with one hand and placing one or more fingers of the other hand under rounded part 39 of lateral section 30. The technician then lifts pull-tab 31 first upwardly so that lateral section 30 is being moved toward corner 46, whereby pointed end 33 of pull-tab 31 pierces tear-line 40. The piercing movement is enabled by rivet 37 acting as a fulcrum and by moustache score 81 acting to concentrate the piercing force toward tear-line 40.
When pull-tab 31 is approximately vertical and corner 46 has been pierced, the technician then pulls pull-tab 31 away from corner 46. In doing so, tear-line 46 proceeds to fracture as it diverges laterally from the respective sides 71, 72 of container 10. Side 98 of raised panel 90, being perpendicular to tab pulling axis 32, prevents the pulling force from deforming temporary portion 23, so that the pulling force is instead directed outwardly to tear-line 40. In addition, the relation of tear-line 40 and double-bend portion 61 acts to further direct the pulling force to tear-line 40. Further, double-bend portion 61 also acts as a spring or cushion, to a degree dependent on various factors such as the material being used, the relative dimensions of double-bend portion 61, etc. Such spring-like action serves as a buffer to prevent pulling force from being transmitted beyond the area near tear-line 40 and acts in cooperation with the tear-line offset form to provide easier and cleaner tearing.
After temporary portion 23 has been removed and welding rods have been used, the technician may wish to reseal the container 10 to prevent intrusion of impurities such as water. Accordingly, a cover cap (not shown) may be provided for covering the opened metal end 14. Such a cap may be formed of plastic, resin, fiber, and/or other material.
The diamond shape of tear-line 40, in combination with the configuration having adjacent sides 91, 92, 93, 94 of raised panel 90 being parallel with respective portions of tear-line 40, also provides for easier removal of temporary portion 23 from permanent portion 22. In a manner similar to other cooperating elements, such relationship between such sides of raised panel 90 and essentially parallel parts of tear-line 40 acts to prevent physical distortion of metal sheet 21 of temporary portion 23 and concentrates pulling force at tear-line 40.
Raised area 83 of temporary portion 23 under pull-tab 31 also acts to concentrate initial tab lifting force at the initial tearing point, especially when such structure is combined with adjacent structural configuration including rivet 37 acting as an ersatz fulcrum, moustache score line 81 acting to direct initial bending of adjacent areas of metal sheet 21 proximate rivet 37, and structural integrity provided by raised panel 90. Further, corners 18, 19 of metal end 14 are preferably formed to align with respective corners 49, 48 of tear line 40, also adding structural support for a tearing operation.
Protective compounds may be applied at either or both of upper surface 87 and/or lower surface 88 of metal sheet 21 in the immediate vicinity of tear-line 40. When tear-line 40 fractures as a result of a welding technician removing temporary portion 23, such protective compounds are caused to be displaced so that they cover at least a portion of the newly-created edge created by the fracture. Such compounds may become exposed by the fracturing process. The protective compounds act to provide additional protection against injury to the welding technician's hand due to possible contact with a sharp edge.
The structural relationship between double-bend portion 61 and tear-line 40 provides additional safety against cuts and similar injuries. For example, when the fracture edge is created by tab-pulling force, the edge bends upwardly into a space under the inner peripheral blunt edge 62 of double-bend portion 61, whereby a technician's hand is prevented from making contact with the fracture edge by blunt edge 62. Such protection is increased when tear-line 51 is disposed slightly outwardly of inner peripheral blunt edge 62, when a thickness 59 of metal sheet 21 is small, and/or when a thickness of vertical portion 58 of tear-line 40 is small, etc. When relative dimensions are made thinner, a large tab pulling force acts to further drive any exposed edge into the space under blunt edge 62, but such thinner material may also cause a sharper fracture edge. By making the boundary 58 vertical thickness as small as practical, a corresponding vertical dimension of potential sharpness also becomes smaller.
While the principles of the invention have been shown and described in connection with specific embodiments, it is to be understood that such embodiments are by way of example and are not limiting.
