The present invention relates to a cap or closure to be applied to a container, with the closure forming means for controlling the discharge of a quantity of material retained within the container.
A number of forms of caps and closures are known for covering the upper end of a container and for selectively controlling the discharge of material from the container. One form of cap includes a sliding member retained by guide rails. The sliding member covers an opening in the cap and is moveable between an open position and a closed position.
U.S. Pat. No. 4,592,480 to Hart et al. shows a tamper-evident cap having a two-part construction with a connecting tearaway tab or strip. In one embodiment, the tearaway tab is formed on one side of the cap and is connected to the slider and to a base portion. The tab can be removed so that the slider may be moved relative to the cap to control discharge from the container.
U.S. Pat. No. 3,355,069 to Miles shows a slideable closure that is retained within rails on a cap. The slider includes an end portion that forms a cutter for shearing off projections in the upper surface to open the cap. In one embodiment shown, a knife edge is fixed on the slider as part of an overmolding process.
U.S. Pat. No. 4,925,067 to Zemlo et al. shows a dispensing cap having a slider secured by rails and moveable in opposite directions to access openings in the surface of the cap. The slider and cap may be made of different materials to control friction between the moving parts.
U.S. Pat. No. 6,102,259 to Tsamourgelis et al. shows a cap for a container having an integrally formed slider that sits between rails on the upper surface of the cap. A pair of elastic arms connect the slider to the cap and serve as a spring that moves the slider to a normally closed position. The slider has a T-shaped end that creates a limit stop for the slider as it moves toward the normally closed position.
In addition, it is known to overmold parts within a plastic structure made of dissimilar materials, such that the final assembly permits the parts to functionally fuse, but not materially fuse. An integrally-molded bearing block assembly formed by an in-mold assembly process is shown in U.S. Pat. No. 5,049,341 to Rubinstein.
A dispensing cap for a container is provided, with the cap adapted to close the open end of the container so as to retain a quantity of material therein and to selectively discharge the material. The cap includes a body portion having a formed sliding track thereon. The sliding track may be defined by a pair of parallel rails, projecting from or otherwise formed on the body. An opening is provided in the body for providing access to the quantity of material within the container. A retention slot is formed adjacent the sliding track. A slider is moveably positioned within the sliding track. A frangible tab is formed on the slider and is engaged within the retention slot to fix the position of the slider prior to removal of the tab. A stop member may be positioned at one end of the sliding track. The stop member serves to engage the slider to prevent movement of the slider within the track, past the stop member. The retention slot may be formed in the stop member. The retention slot may alternatively be formed within one of the rails, with the frangible tab extending from the slider in a direction transverse to the rail.
A method of forming a cap for a container is also contemplated, comprising the steps of forming a container body having a sliding track thereon. The sliding track may be defined by a pair of rails positioned on opposite sides of the body portion. The upper surface of the body is formed with an opening for providing access to a quantity of material within the container on which the cap is to be positioned. A retention slot is formed adjacent the sliding track. A slider is moveably positioned within the sliding track for selectively opening and closing the body opening. A frangible tab may be formed on the slider at a position for engagement within the retention slot to fix the position of the slider. The body of the cap may be formed by an injection molding process. Further, the slider may be molded by an in-mold assembly within the formed body portion. The frangible tab is integrally formed with the slider and may be formed during the in-mold assembly of the slider within the retention slot.
Other features of the present invention will become apparent from the detailed description to follow, taken in conjunction with the accompanying drawings.
For the purpose of illustrating the invention, the drawings show forms that are presently preferred. It should be understood that the invention is not limited to the precise arrangements and instrumentalities shown in the drawings.
In the figures, where like numerals identify like elements, there is shown a number of embodiments of a dispensing cap for a container or the like (not shown). It is contemplated that the container may be separately formed from the dispensing cap, with structures provided on the cap for adhering the cap to the open end of the container and to retain the quantity of material to be stored within the container. Alternatively, the cap may be integrally formed with the container body or otherwise secured to the container.
In
The slider 14 is normally positioned within the sliding track formed by the rails 16, 18. A frangible tab 28 is positioned at one end of the slider 14, as shown in
As shown in
As graphically shown in
As illustrated in
An in-mold assembly of the cap 10 is accomplished by a strategic resin selection for the body portion 12 and the slider 14. For example, the material of the body can be chosen to have a melt temperature higher than the material of the slider. Thus, the slider material does not fuse with or chemically bond to the material of the body, or its associated rails, during the molding of the slider. It is contemplated that the body portion of the cap may be formed from polypropylene, which may have a talc filling therein. This type material will assist in marrying the cap with the container and allow for the use of ultrasonic bonding of elements, if desired. This type material is also compatible with various type spices and other products. The talc is used to deter excessive shrinkage and can contribute to proper adhesion. The slider is preferably made from a crystal polystyrene. This type material is compatible with the polypropylene of the cap in the in-mold assembly process. Polystyrene and polypropylene tend to not create a molecular bond when molded against one another. Although the melting temperatures of these materials are relatively close, the lack of a molecular bond during the molding process is contemplated to produce the desired freedom between the body and slider for in-mold assembly. In addition, the use of a polystyrene for the slider is contemplated to provide the tab portion of the slider with the appropriate level of stiffness so as to be easily broken off when opening is desired.
In the in-mold assembly of the cap 10, the frangible tab 28 of the slider 14 is formed within the retention slot 30 of the stop member 26. The tab 28 is integrally formed with the slider 14. A frangible extension connects the tab 28 forming a T-shaped projection. The slider 14 is formed under the rails 16, 18 during the in-mold assembly process and the tab 28 is formed on the opposite side of the stop member 26 from the slider 14. Thus, deformation of the slider 14 is not required in order to assemble the cap 10. A destructive force is required to remove the tab 28 in order to free the slider 14 from a locked position stop member 26. The tab 28 is preferably formed in this manner to identify tampering.
In
In the embodiment shown in
In
The cap 210 of
The present invention has been described and illustrated with respect to a number of exemplary embodiments thereof. It should be understood by those skilled in the art from the foregoing that various other changes, omissions and additions may be made therein, without departing from the spirit and scope of the present invention, with the scope of the present invention being described by the foregoing claims.
The present application claims the benefit of the filing date from U.S. Provisional application No. 61/173,712, filed Apr. 29, 2009.
Number | Date | Country | |
---|---|---|---|
61173712 | Apr 2009 | US |