PRODUCT DISPENSER AND SECUREMENT CUP

Abstract

A lipstick cup for securing a lipstick cylinder or bullet, suitable for a soft lipstick formula, having a cylindrical body with a base and a sidewall having axially-arranged ribs distributed substantially evenly around the inner circumference of the sidewall near the base, that extending radially inwardly from the sidewall, and a plurality of shallow undercut structures distributed substantially evenly around the circumference of the sidewall, disposed circumferentially between the pairs of adjacent ribs, and tapering inwardly from the inner surface of the sidewall toward the base to provide an undersurface. The plurality of ribs displace and compress a portion of the material of the lipstick composition circumferentially toward and between the undersurface of the shallow undercut structures, and the base, for preventing the product from being dislodged from the cup.

Claims

1. An injection-molded lipstick cup for a cylinder of lipstick, used in a lipstick case, the cup comprising: i) a cylindrical body including a base and a sidewall having an inner surface defining an interior opening adapted for receiving a base portion of the lipstick, ii) a plurality of axially-arranged ribs distributed substantially evenly around the circumference of the sidewall and proximate the base, extending radially inwardly from the inner surface of the sidewall, and iii) a plurality of shallow undercut structures distributed substantially evenly around the circumference of the sidewall, disposed circumferentially between adjacent ribs, the shallow undercut structure having a surface facing radially inwardly and tapering down and away from the inner surface of the sidewall, toward the base, and to a lower extended ledge, and an undersurface that extends radially outwardly from lower extended ledge to the inner surface of the sidewall, that faces toward the base.

2. The injection-molded lipstick cup according to claim 1 where the curved lower extended ledge has a lateral curvature that is substantially the same as the curvature of the inside surface of the sidewall.

3. The lipstick cup according to claim 1 wherein the plurality of ribs displace and compress a portion of the material of the base portion of the lipstick circumferentially toward and between the undersurface of the shallow undercut structures and the base, to prevent the lipstick from being dislodged from the cup.

4. The lipstick cup according to claim 1 wherein the inwardly-facing surface of the undercut structure is a concave surface.

5. The lipstick cup according to claim 4 wherein the inward-facing surface of the undercut structure has a lateral curvature that follows the curvature of the inside surface of the sidewall, and a thickness that is substantially the same from one side laterally to the opposite side.

6. The lipstick cup according to claim 5 wherein the undercut structure has an increasing thickness, from a top end toward the lower extended ledge.

7. The lipstick cup according to claim 1 wherein the inward-facing surface of the undercut structure, is about 30 degrees or less, including about 20 degrees or less, and about 15 degrees or less, from the inner surface of the sidewall.

8. The lipstick cup according to claim 1 wherein the holder is made by an injection molding process and equipment.

9. The lipstick cup according to claim 8 wherein the cup can be formed of a thermoplastic material using an injection molding process.

10. The lipstick cup according to claim 1 wherein the shallow undercut structure has a generally pyramidal shape.

11. The lipstick cup according to claim 1 wherein the shallow undercut structure has a frustum shape.

12. The lipstick cup according to claim 1 wherein the shallow undercut structure has upper curved shape.

13. A lipstick dispenser for a cylinder of lipstick, the lipstick dispenser comprising a housing, the cylinder of lipstick within the housing moveable between a storage position and a user position, a lipstick cup for receiving the cylinder of lipstick according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above description, as well as further objects, features and advantages of the present invention will be more fully understood with reference to the following detailed description of a product dispenser and holder, when taken in conjunction with the accompanying drawings, wherein:

[0028] FIG. 1 shows a perspective, cut-away view of a lipstick product dispenser to show a lipstick cup having a plurality of undercut structures disposed on the inner surface of its sidewalls, for holding a lipstick cylinder.

[0029] FIG. 2 shows a top plan view the lipstick cup, viewed along line 2-2 of FIG. 1.

[0030] FIG. 3 shows a sectional view of the lipstick cup, viewed along line 3-3 of FIG. 2.

[0031] FIG. 4 shows detailed view of the undercut structure of FIG. 3.

[0032] FIG. 5 shows a horizontal sectional view of the undercut structure of FIG. 4, viewed along line 5-5.

[0033] FIG. 6 shows a vertical sectional view of the undercut structure of FIG. 4, viewed along line 6-6.

[0034] FIG. 7 shows another embodiment of an undercut structure having a frustum profile.

[0035] FIG. 8 shows a horizontal sectional view of the undercut structure of FIG. 7, viewed along line 8-8.

[0036] FIG. 9 shows a vertical sectional view of the undercut structure of FIG. 7, viewed along line 9-9.

[0037] FIG. 10 shows another embodiment of the undercut structures with a curved profile.

[0038] FIG. 11 shows a horizontal sectional view of the undercut structure of FIG. 10, viewed along line 11-11.

[0039] FIG. 12 shows a vertical sectional view of the undercut structure of FIG. 10, viewed along line 12-12.

DETAILED DESCRIPTION OF THE INVENTION

[0040] Referring to the drawings, wherein like reference numerals represent like elements, there is shown in FIGS. 1 through 3, a lipstick dispenser 1 having an outer body 2 and a holder or cup 10 for securing the base end of a lipstick cylinder L (shown in silhouette to not obscure the details of the cup). The cup 10 includes an annular sidewall 12 that defines a top opening 16, and a base 14 that cooperates with the sidewall 12 to define an inner cylindrical space 18 for holding the base end of a lipstick cylinder L. The cup 10 also has eight equally-spaced, axially-aligned ribs 20 that are distributed substantially evenly around the circumference of the inner surface of the annular sidewall 12, proximate the base 14. The ribs 20 extend a distance radially inwardly from the annular sidewall 12, toward the centerline 100 of the cup 10, and the inner edge of each rib 20 is rounded. The upper end 22 of the ribs 20 extend upward toward the top opening 16, and curves toward the sidewall 12. The ribs 20 press into the bottom and the outer peripheral surface of the lipstick cylinder L as the lipstick cylinder is inserted axially into the inner cylindrical space 18 to the base 14, to aid retention of the lipstick cylinder L within and prevent its axial rotation relative to the cup 10.

[0041] The cup 10 also includes eight shallow undercut structures 30 extending from the inner surface of the sidewall 12, and spaced equally between adjacent ribs 20. The undercut structures 30 are positioned a distance axially from the base 14, at a height position intermediate the height of upper end 22 of the ribs 20. In the illustrated embodiment, the shallow undercut structures 30 are positioned about half-way up the height of the sidewall, although a lightly lower or higher height can be used. The inward-facing surface 32 of the shallow undercut structures 30 face radially inwardly and taper from an upper edge 31, down and away from the sidewall 12 to a lower extended ledge 34.

[0042] An embodiment of the undercut structure is shown in FIGS. 4 through 6, and has a generally pyramidal shape. The inwardly-facing surface 32 of the undercut structure 30 is substantially concave, as illustrated in FIG. 5. The inward-facing surface 32 of the undercut structure 30 has a lateral curvature that follows the curvature of the inside surface of the sidewall 12, and the thickness of the undercut structure 30 laterally, from side to side, is substantially the same. The inward-facing surface 32 of the undercut structure 30 tapers inwardly, and the undercut structure 30 has increasing thickness, from the top end 31, toward a lower extended ledge 34. Typically, the inward taper of the surface 32, from vertical or the inner surface of the sidewall 12, is about 30 degrees or less, including about 20 degrees or less, and about 15 degrees or less

[0043] The lower extended ledge 34 extends radially inwardly by a substantially equal distance from the sidewall 12 along its circumferential length. As shown in FIG. 5, the curved, lower extended ledge 34 has a lateral curvature that follows the curvature of the inside surface of the sidewall 12, and has substantially the same distance radially from the inside surface of the sidewall 12, shown as distance T.

[0044] The inward-facing surface 32 of the undercut structure 30 includes an upper portion 33 that tapers downwardly from the upper edge 31 (shown as a point) and intersects with an intermediate portion 35, which then intersects with a bottom portion 37 that extends to the lower extended ledge 34. The tapering of the inward-facing surface 32 prevents tearing of the base structure of the lipstick cylinder L as the material of the lipstick cylinder L slides down the inward-facing surface 32, and over and past the undercut structure 30.

[0045] An undersurface 36 extends from the lower extended ledge 34 back, or radially outwardly, to the inner surface of the sidewall 12 along line 38, below the undercut structure 30. The undersurface 36 faces downward toward the base 14, and is typically angled from horizontal sufficiently to provide a functional benefit of the securement or retention of the lipstick cylinder within the cup 10, described below.

[0046] The angular displacement 1 (FIG. 2) of an undersurface 36 along the circumference of the sidewall 12, is typically about 15-30 degrees, and more typically about 20-25 degrees.

[0047] Without being bound by any theory, the pressing of the lipstick cylinder L into the inner cylindrical space 18 forces the ribs 20 into the outer circumference of the lipstick L, which displaces the semi-solid waxy lipstick material into the space between the ribs 20. It is believed that the slight tapering and shallow lower extended ledge 34 compresses slightly and gently the semi-solid, waxy material of the lipstick cylinder L that passes along the inwardly-facing surface 32. After the waxy material of the lipstick cylinder LA passes below the curved, lower extended ledge 34, it then expands radially outwardly along and/or under the undersurface 36 toward the inner surface of the sidewall 12, without substantially deterioration of the structure of the lipstick. The plurality of undersurfaces 36 then present barrier walls that confront the lipstick material, that has expanded below the undersurface 36, to resist axial movement of the lipstick cylinder L away from the base 14, and prevent the lipstick cylinder from being dislodged from the cup 10. The undersurfaces of the present invention permit the lipstick cylinder to pass over and below its extending structure, without breaking, fracturing, or cracking the outer surface of the lipstick cylinder, particularly with soft lipstick formulations.

[0048] A further embodiment of an undercut structure is shown in FIGS. 7 through 9, as an undercut structure 130 having a frustum-shaped vertical profile, with an inwardly-facing surface 132. The inwardly-facing surface 132 can include an upper portion 133 that tapers from along the upped edge 131, and down and away the sidewall surface 12, to intersect an optional intermediate portion 135, which intersects a bottom portion 137 that has a lower extended ledge 134. An undersurface 136 extends radially outwardly from the curved lower extended ledge 134 to join the wall surface along line 138, similar to the undersurface 36 described above.

[0049] A further embodiment of an undercut structure is shown in FIGS. 10 through 12, an undercut structure 230 having an upper curved shape or vertical profile, with an inwardly-facing surface 232. The inwardly-facing surface 232 can include an upper portion 233 that tapers downwardly from a curved top edge 231, to intersect an optional intermediate portion 235, which intersects a bottom portion 237 that has a lower extended ledge 234. An undersurface 236 extends radially outwardly from the curved lower extended ledge 234 to join the wall surface along line 238, similar to the undersurface 36 described above.

[0050] The cup 10 can be conveniently formed of a thermoplastic material using an injection molding process. The shallow undercut structures 30 have sufficient radial thickness to resist upward, axial movement of the lipstick cylinder, yet are sufficiently thin to permit the undercut to clear the mold following injection molding. The dimensions and geometry presents a very slight undercut (termed a mini undercut) which permits the molded part to be force ejected when using a normal, non-undercut cup injection mold, eliminating the expense and complexity of molding a typical undercut-style design which requires a special, more difficult mold structure with core protrusion coming from both the core side and the cavity side of the mold.

[0051] While the illustrated embodiment shows eight equally spaced ribs 20 with eight equally spaced undercut structures 30, the number of ribs and undercut structures, respectively, can include 6-10, and either a larger number of ribs and undercut structures, such as 9-12, can be provided, or a smaller number such as 4-7, as is suitable for a particular lipstick composition.

[0052] The invention also includes a lipstick dispenser for a cylinder of lipstick, the lipstick dispenser comprising a housing, the cylinder of lipstick within the housing moveable between a storage position and a user position, and a lipstick cup for receiving the cylinder of lipstick as described herein. The lipstick dispenser can also include a cap enclosing one end of said housing when said product is in the storage position.

[0053] Although the invention herein has been described with reference to particular embodiments, it is to be understood that the embodiments are merely illustrative of the principles and application of the present invention. It is therefore to be understood that numerous modifications may be made to the embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the claims.