This invention relates to a push-up dispenser for solid and viscous products. More particularly this invention relates to a dispenser which can be maintained at the dispensing position by a gripping of the dispenser walls.
Dispensing containers are used with regard to a number of cosmetic products. These include solid products such as lipsticks, deodorants and antiperspirants and various viscous lotion and gel products such as body lotions and gels, sunscreens, and deodorant and antiperspirant lotions and gels. Lipsticks are usually in a cylindrical form with a circular cross-section and are in a tubular container with a closure. The lipsticks are either manually elevated in the container for use or utilize a push-up mechanism on the container. Deodorants and antiperspirants usually use a mechanism to elevate the solid, lotion or gel product for use. This mechanism typically is located in the base of the dispenser and consists of a platform elevator that supports the deodorant or antiperspirant, an attached screw, and a disc wheel grip on the other end of the attached screw to rotate the screw and thereby to raise and lower the platform elevator. Deodorants and antiperspirants also use mechanisms that are located in the wall of the container part of the dispenser.
These prior art dispensers are all useful and effective dispensers. However they consist of six or more parts that must be produced and assembled. The problem is to how best reduce the number of parts and the cost of the dispensers. One solution is to use a push-up dispenser. However the problem then is how to maintain the product at a selected level in the dispenser while the product is being applied to a surface. One technique is to have a finger hold the product support at a given level during the application of the product. This is exemplified in U.S. Pat. No. 3,397,027; U.S. Pat. No. 4,621,935 and U.S. Pat. No. 5,944,434. In each of these patents a person pushes the supported product upward for dispensing and then maintains the finger in contact with the product support during dispensing. This maintains the product at the application level and so that it does not recede into the container. In another technique the product support is mechanically maintained at a given level by a friction contact of the product support with the wall of the dispenser. This is exemplified by U.S. Pat. No. 1,850,934; U.S. Pat. No. 5,286,126; U.S. Pat. No. 5,897,263; U.S. Pat. No. 4,621,935 and U.S. Pat. No. 4,708,507. These are effective as long as a medium to high application force is not used. When such a force is used the product will recede back into the container portion of the dispenser.
The present invention solves this problem through the use of a dispenser with only three primary parts and with the dispenser having a positive locking mechanism for the product support during product application. This prevents the product support and the product slipping down into the container during use.
The present dispenser is adapted to minimize the parts that are needed while providing a dispenser that is easy to use. This also reduces the number of parts that need to be assembled. The dispenser comprises a first sleeve which is substantially open at the top and the bottom. A product support that includes a second sleeve which is received in the first sleeve. The second sleeve has a lower surface that is adapted to be contacted by a person's finger to adjust the second sleeve in the first sleeve. The inner surface of the first sleeve and the outer surface of the second sleeve have interfering structures such that when they are in contact the second sleeve is maintained in a set orientation, one to the other. This contact is the result of the first sleeve being pushed into contact with the second sleeve by the holding and gripping of the first sleeve. This contact can be enhanced through one or more apertures in the first sleeve walls to increase the flexibility of the first sleeve and consequently it's flexing against the second sleeve.
The interfering structure can be of any kind where the second sleeve can be maintained at a plurality of positions relative to the first sleeve. This can be accomplished by mating serrations on the inner surface of the first sleeve and on the outer surface of the second sleeve; serrations on the inner surface of the first sleeve and a mating projection on the outer surface of the second sleeve; and serrations on the outer surface of the second sleeve and a mating projection on the inner surface of the first sleeve. Other structures that produce the same result would be considered to be equivalent structures.
In use a closure is removed from the dispenser and the second sleeve pushed upward to a position to dispense the product. Then by a normal gripping of the first sleeve to hold it for use, the first sleeve flexes and the first and second sleeves become locked together temporarily whereby the second sleeve cannot recede within the first sleeve during use. After use by relaxing the gripping the first sleeve and the second sleeve become unlocked, the closure is placed onto the dispenser, and the second sleeve receded into the first sleeve. If the product is too high the closure as it is being put into place will contact the product and move it downward into the first sleeve along with the second sleeve on which it is supported.
The primary parts of the dispenser are the first sleeve, the second sleeve and the closure. Conventional dispensers can have five or more primary parts.
The invention will be described in more detail in its preferred embodiments with reference to Figures in the drawings. Modifications can be made to the disclosed embodiments but all such modifications are with the concept of the present invention.
The recess 32 of the second sleeve 16 coordinates with the aperture 22 of the first sleeve to increase the ease of the moving the second sleeve 16 upward in the first sleeve 12. In the preferred embodiment there is a companion recess 33 on the opposite side surface as shown in
The parts for the dispenser 10 can be made by conventional injection molding processes using conventional thermoplastics. Useful thermoplastics are the polymers and copolymers of ethylene, propylene, butene and butadiene and various polyesters such as polyethylene terephthalate.
The dispenser 10 can be produced by a top filling technique where the second sleeve 16 is lowered in first sleeve 12 to a level that will hold a set volume of product. This also will be related to a particular gram weight. The first sleeve 12 is filled to about the upper edge of the first sleeve 12 with the liquid heated product. The inner volume of the second sleeve also will contain some of the product. The closure 14 then is placed onto the first sleeve 12 and the filled dispenser inverted and cooled to solidify the heated liquid product. The upper surface of the solidified product will have a shape that is complementary to the inner surface of the closure 14.
To use the dispenser 10 a person removes the closure 14, pushes up on the bottom surface of second sleeve 16 to raise the product above the upper edge of the first sleeve 12. The outer surface of the first sleeve 12 is gripped at an applicating grip strength which will cause the cooperating interference structure on the inner surface of the first sleeve 12 to contact the interference structure on the outer surface of the second sleeve 16. This will temporarily lock the sleeves to a set orientation, one to the other. The product then is applied and after application the gripping is released to a lighter holding grip whereby the first sleeve 12 and the second sleeve 16 unlock. The second sleeve 16 can be retracted into the first sleeve 12 with the product being stored within the first sleeve 12. The closure 14 is then put onto first sleeve 12. The closure being put into place can assist in the receding of the second sleeve and product into the first sleeve 12.