Dispensing closure

Abstract

A plastic dispensing closure includes an elongated dispensing spout that defines an interior passage and has a distal end terminating in a rim. A sealing member is integral with the dispensing spout and is frangibly connected to the distal end of the dispensing spout by frangible connecting structure in order to seal the interior passage and prevent fluid from leaking out of the closure before it is opened. A lever arm that is integral with the sealing member is oriented so as to extend upwardly from the sealing member. The frangible connecting structure is advantageously constructed and arranged to rupture when a predetermined torque is applied to the lever arm. The predetermined torque is calculated so as to minimize the likelihood of the closure being opened accidentally, while at the same time being convenient for a consumer to open.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to the field of plastic closures for containers. More specifically, this invention relates to an improved dispensing closure with an elongated dispensing spout having a tamper-evident seal provided thereon.

2. Description of the Related Technology

One common type of dispensing closure design is characterized by an elongated, generally tapered dispensing spout having a distal end that is sealed before it is opened by a consumer. Typically, the consumer is instructed to make the dispensing spout operable by cutting it with a scissors or sharp knife. While such closures have operated effectively to some extent, they have a number of inherent drawbacks associated with them. For instance, a consumer may injure his or herself with the scissors or the knife. This is particularly a danger for the elderly and the very young. In addition, dispensing spouts that have been severed or cut generally end up having a sharp edge that has the potential of cutting the consumer or other bystanders or that makes it unpleasant to use the dispenser. For example, if the purpose of the dispensing closure is to dispense hair colorant, a sharp edge on the end of the dispensing spout is likely to abrade the consumer's scalp. Sometimes, the consumer will partially cut the dispensing spout and then forcefully rip a partially severed spout end away from the rest of the spout, which produces a jagged, rough edge that is unacceptable for many purposes.

Users of such conventional tapered spout dispensing closures also often had difficulty in determining the proper position and angle of the cut. With a tapered dispensing spout, cutting at a location that is too close to the distal end of the spout will produce an orifice that is too small, while cutting at a location that is too far from the distal end of the spout creates an orifice that is too large. The very functionality of the dispensing spout, then, is placed in doubt when the decision as to where to cut is left to the consumer.

In order to address such issues, a number of dispensing closures have been proposed that include an integral sealing plug and an attached gripping arm at the distal end of the dispensing spout that are frangibly attached to the dispensing spout so that it will be torn away from the closure upon the application of a pulling or a twisting force to the gripping arm by a consumer. For example, U.S. Pat. No. 5,586,672 to Schneider et al. discloses a dispensing closure with a frangibly attached cap that is designed to be twisted apart from the dispensing spout of the closure by the application of a radial torque using a tool that is incorporated into a closure cap.

While such designs had merit in concept, their commercial popularity has been limited because they are especially prone to failure by opening prematurely, such as when the container to which the closure is mounted is dropped on the floor by the consumer or bumped against a wall or other surface. In order to prevent such premature openings from accidentally occurring, the strength of the frangible connection between the sealing plug and the dispensing spout must be strengthened. However, if the strength of the frangible connection is made too great, the closure will be difficult to open by the consumer and/or it may not open properly at all.

A need exists for an improved dispensing closure that is designed to be resistant to premature accidental opening, that is simple for a consumer to open, and that opens without requiring undue strain or trouble on behalf of the consumer.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the invention to provide an improved dispensing closure that is designed to be resistant to premature accidental opening, that is simple for a consumer to open, and that opens without requiring undue strain or trouble on behalf of the consumer.

In order to achieve the above and other objects of the invention, a plastic dispensing closure according to a first aspect of the invention includes an elongated dispensing spout, the dispensing spout defining an interior passage and having a distal end; a sealing member that is integral with the dispensing spout, the sealing member being frangibly connected to the distal end of the dispensing spout by frangible connecting structure so as to seal the interior passage and prevent fluid from leaking therefrom; a lever arm integral with the sealing member, the lever arm extending upwardly from said sealing member; and wherein said frangible connecting structure is constructed and arranged to rupture when a predetermined torque is applied to said lever arm, and wherein said predetermined torque is within a range of about 0.01 foot pounds to about 0.25 foot pounds.

These and various other advantages and features of novelty that characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a dispensing closure that is constructed according to a preferred embodiment of the invention;

FIG. 2 is a fragmentary side elevational view of a portion of the closure that is depicted in FIG. 1;

FIG. 3 is a cross-sectional view taken along the plane indicated as 3-3 in FIG. 2;

FIG. 4 is a cross-sectional view taken along the plane indicated as 4-4 in FIG. 6;

FIG. 5 is a top elevational view of the portion of the closure that is depicted in FIG. 2; and

FIG. 6 is a magnified view of the area that is indicated by the circle in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views, and referring in particular to FIG. 1, a plastic dispensing closure 10 that is constructed according to a preferred embodiment of the invention includes a main body portion 12 having a downwardly depending apron 14 on which a number of gripping ribs 16 are defined. The main body portion 12 is conventional in that it includes conventional internal structure that enables it to be mounted on to a container. In the preferred embodiment, main body portion 12 includes a circumferential inner surface of the apron 14 that has at least one thread defined thereon for mating with a threaded finish portion of a container.

As FIG. 1 shows, dispensing closure 10 includes an elongated dispensing spout 18 that generally has the shape of an inverted cone, being substantially symmetrical about a longitudinal axis 20, shown in FIG. 2, being thicker at a lower end thereof that is unitary with the main body portion 12, and being tapered so as to be thinner at an upper end thereof terminating at a distal end 22. Preferably, elongated dispensing spout 18 is tapered at an angle {acute over (ω)} that is within a range of about 1° to about 15°, with a more preferred range of about 2° to about 10°. Elongated dispensing spout 18 defines an internal passage 24, best shown in FIG. 3, for constraining a liquid or gel material for movement therein from a container to which dispensing closure 10 is mounted to the distal end 22.

In the period of time between the fabrication of dispensing closure 10 and opening of the dispensing closure 10 by a consumer the distal end 22 of the elongated dispensing spout 18 is sealed so that any liquid or gel material within the internal passage 24 will not be permitted to escape from the dispensing closure 10. As is best shown in FIG. 6, a sealing member 26 is frangibly connected to the distal end 22 of the dispensing spout 18 by frangible connecting structure so as to seal the interior passage 24 and prevent fluid from leaking therefrom. Sealing member 26 is integral and more preferably unitary with both the elongated dispensing spout 18 and a lever arm 38 that extends upwardly from the sealing member 26, as will be discussed in greater detail below. Preferably, the sealing member 26, the dispensing spout 18, the lever arm 38 and the main body portion 12 are fabricated by a one step injection molding process from the same plastic material, which in the preferred embodiment is high-density polyethylene.

As is best shown in FIG. 6, the elongated dispensing spout 18 terminates at its distal end 22 at a peripheral rim 28, which in the preferred embodiment of the invention is substantially circular when viewed from top plan as is depicted in FIG. 5. The conical transition surface 30 angles downwardly and inwardly in the shape of a section of an inverted cone from the peripheral rim 28 to a location where frangible connection structure 32 secures the elongated dispensing spout 18 to the sealing member 26. In the preferred embodiment, the frangible connecting structure 32 is embodied as a frangible web 34 has a predetermined minimum thickness that is calculated to achieve the force opening characteristics described below. Preferably, this minimum thickness is within a range of about 0.008 inches to about 0.025 inches. In addition, a lower transition surface in the shape of a portion of an upright cone extends from an inner wall of the elongated dispensing spout 18 to the frangible connecting structure 32. Preferably, the conical transition surface 30 is substantially symmetrical about the longitudinal axis 20 of the elongated dispensing spout 18 and is disposed of an angle α with respect to axis 20 that is within a range of about 45° to about 75°. More preferably, angle α is within a range of about 55° to about 65°, with a most preferred value of about 60°.

In addition, lower transition surface 36 is also preferably substantially symmetrical about the longitudinal axis 20 and, as is shown in FIG. 6 is disposed that an angle β that is within a range of about 75° to about 85°, with a preferable value of about 80°. By tapering both the conical transition surface 30 and the lower transition surface 36, a force magnification effect is achieved in the area of the frangible connecting structure 32 during opening, which contributes to a clean, trouble-free opening with no ragged edges being produced.

As is shown in all of the figures, a lever arm 38 is integral and preferably unitary with the sealing member 26 and extends vertically upwardly with respect to the sealing member 26 for a predetermined distance H_L, which is preferably within a range of about 0.2 inches to about 1.0 inch and more preferably within a range of about 0.25 inches to about 0.5 inches. Most preferably, predetermined distance H_L is within a range of about 0.3 inches to about 0.4 inches. Lever arm 38 is preferably fabricated so as to be relatively stiff so that it will not bend or deflect during manipulation by a consumer to open the closure 10. Lever arm 38 is preferably substantially rectangular or oblong in transverse cross-section, having a width W_L, shown in FIG. 3, that is preferably greater than a depth D_L, shown in FIG. 4. Preferably, the width W_L is preferably within a range of about 0.04 inches to about 0.12 inches and is more preferably within a range of about 0.08 inches to about 0.11 inches. One benefit of having the width of the lever arm 38 greater than the depth is that it will promote more effective gripping of the lever arm 38 by the consumer. It will also tend to lead the consumer to want to exert torque to rotate the lever arm 38 in a direction that is orthogonal to the broad side surface of the lever arm 38 when opening the closure 10. While in the preferred embodiment the web 34 forming the frangible connecting structure 32 is preferably substantially symmetrical in thickness and in shape about the longitudinal axis 20, alternative embodiments of the invention may take advantage of this tendency by making the frangible connecting structure 32 more or less likely to rupture in the direction that the consumer is likely to attempt to open the closure 10.

According to one important aspect of the invention, the amount of force that is required to be applied to the lever arm 38 in order to rupture the frangible connecting structure 32 is maintained within a preferred predetermined range that requires a great enough force so as to minimize the possibility of the closure 10 being opened accidentally by the consumer or in the packaging, distribution or retail process. The preferred predetermined range further is limited so as to not require so much force that it is difficult for the consumer to open the closure 10 or that significant deflection of the plastic material in the closure 10 is required during the opening process. Preferably, the preferred predetermined force range is measured as the amount of torque, specifically torque applied in a longitudinal plane, that must be applied to the lever arm 38 to deflect the lever arm 38 away from its neutral position that is symmetrical about the longitudinal axis 20 to the extent that is necessary to cause the web 34 of plastic material forming the frangible connecting structure 32 to rupture. This type of torque will for purposes of this document be described as longitudinal torque.

Preferably, the frangible connecting structure 32 is constructed and arranged to rupture when a predetermined longitudinal torque that is within a range of about 0.010 foot pounds to about 0.250 foot pounds is applied to the lever arm 38. More preferably, the predetermined longitudinal torque is within a range of about 0.020 foot pounds to about 0.150 foot pounds. Most preferably, the predetermined longitudinal torque is within a range of about 0.040 foot pounds to about 0.115 foot pounds.

As the consumer exerts such torque on the lever arm 38, maximum stress and consequently strain is applied to those areas of the frangible connecting structure 32 that intersect the longitudinal plane in which the torque is being applied. One of those areas will be in tension, while the opposing area will be in compression. The initial rupture of the frangible connecting structure 32 is expected to occur in the area described above that is under tension, and the rupture is then expected to propagate both clockwise and counterclockwise as viewed from the top plan view provided in FIG. 5 until the entire frangible connecting structure 32 has been breached and the lever arm 38 and the attached sealing member 26 may be removed from the rest of the dispensing closure 10. After removal of the lever arm 38 and the sealing member 26, the dispensing closure 10 may be used by the consumer to dispense the contents of the container to which the dispensing closure 10 is attached.

It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

1. A plastic dispensing closure, comprising:

an elongated dispensing spout, said dispensing spout defining an interior passage and having a distal end;

a sealing member that is integral with said dispensing spout, said sealing member being frangibly connected to said distal end of said dispensing spout by frangible connecting structure so as to seal said interior passage and prevent fluid from leaking therefrom;

a lever arm integral with said sealing member, said lever arm extending upwardly from said sealing member; and

wherein said frangible connecting structure is constructed and arranged to rupture when a predetermined longitudinal torque is applied to said lever arm, and wherein said predetermined longitudinal torque is within a range of about 0.01 foot pounds to about 0.25 foot pounds.

2. A plastic dispensing closure according to claim 1, wherein said sealing member is unitary with said elongated dispensing spout.

3. A plastic dispensing closure according to claim 2, wherein said lever arm is unitary with said sealing member.

4. A plastic dispensing closure according to claim 1, wherein said lever arm is unitary with said sealing member.

5. A plastic dispensing closure according to claim 1, wherein said lever arm is unitary with said elongated dispensing spout.

6. A plastic dispensing closure according to claim 1, wherein said dispensing spout, said sealing member and said lever arm are integrally molded from a plastic material in a one step molding process.

7. A plastic dispensing closure according to claim 6, wherein said plastic material comprises high-density polyethylene.

8. A plastic dispensing closure according to claim 1, wherein said elongated dispensing spout terminates in a distal rim, and wherein said sealing member is recessed with respect to said distal rim.

9. A plastic dispensing closure according to claim 8, wherein said distal end of said dispensing spout further comprises a conical transition surface between said distal rim and said sealing member, and wherein said frangible connecting structure comprises a thin web of material between said conical transition surface and said sealing member.

10. A plastic dispensing closure according to claim 9, wherein said frangible connecting structure is fabricated by a process consisting of injection molding.

11. A plastic dispensing closure according to claim 1, wherein said lever arm has a length that is within a range of about 0.2 inches to about 1.0 inches.

12. A plastic dispensing closure according to claim 11, wherein said lever arm has a length that is within a range of about 0.25 inches to about 0.5 inches.

13. A plastic dispensing closure according to claim 12, wherein said lever arm has a length that is within a range of about 0.3 inches to about 0.4 inches.

14. A plastic dispensing closure according to claim 1, wherein said sealing member and said frangible connecting structure are constructed so as to define a dispensing orifice after removal of said lever arm and said sealing member from said dispensing closure, and wherein said dispensing orifice has a diameter that is within a range of about 0.01 inches to about 0.3 inches.

15. A plastic dispensing closure according to claim 14, wherein said dispensing orifice has a diameter that is within a range of about 0.05 inches to about 0.2 inches.

16. A plastic dispensing closure according to claim 8, wherein said sealing member is recessed with respect to said distal rim of a longitudinal distance of at least 0.040 inches.

17. A plastic dispensing closure according to claim 1, wherein said predetermined longitudinal torque is within a range of about 0.020 foot pounds to about 0.150 foot pounds.

18. A plastic dispensing closure according to claim 17, wherein said predetermined longitudinal torque is within a range of about 0.04 foot pounds to about 0.115 foot pounds.