The present invention relates to improvements for a container that houses a stick product. More particularly, the invention relates to a container that enables a stick product in a holder cup to be moved between an extended position, where the product within the holder cup is capable of being applied by a consumer, and a retracted position. The invention also relates to methods of assembling such a container.
A well known type of container for a stick product features a base that is connected to a cylindrical inner body, and a cam sleeve that is placed around the inner body, such that the cam sleeve and inner body can rotate with respect to each other. The inner body is hollow, and has a wall with at least one longitudinal slot that extends through the wall. The cam sleeve has an inner wall that features at least one helical groove that extends along a substantial length of the inner wall. A holder cup for a stick product is provided, and comprises at least one cam follower in the form of a lug. When the holder cup is fitted into the inner body, the lug extends through the longitudinal slot of the inner body to engage the helical groove of the cam sleeve. In this arrangement, when the inner body is rotated relative to the cam sleeve, then the helical groove of the cam sleeve applies pressure to the lug of the holder cup, which drives the holder cup up or down in the inner body, while the lugs ride in the longitudinal slot. In this way, the stick product is moved between an advanced position and a retracted position.
The holder cup is typically assembled into the top of the inner body. However, the lugs of the holder cup extend beyond the perimeter of the inner body, and the top of the inner body may not have enough stretch or flexibility to allow the lugs to pass through. In fact, to facilitate the insertion of the inner body into the cam sleeve, the top, outer edge of a conventional inner body is tapered, and this taper adds stiffness around the top perimeter of the inner body. Also, even if the lugs of the holder cup could be forced into the top of the inner body, both the inner body and lugs are likely to suffer some damage. To alleviate this problem, some inner bodies (50; see
After the holder cup is inserted into the top of the inner body, the inner body and cam sleeve are assembled by inserting the top of the inner body into the bottom of the cam sleeve. As noted above, the secondary slot and the gap in the top perimeter of a conventional inner body allow the top portion of the inner body to flex. Also, the outer edge of the inner body is tapered. Both of these features facilitate the insertion of the inner body into the cam sleeve. However, before the top of the inner body can flex inwardly, the holder cup must be lowered to its retracted position. There are at least two disadvantages to this. First, it is just an extra step in the assembly process. Second, it would be advantageous for a product filler to receive the inner body-holder cup subassembly with the holder cup in its extended position, ready to fill. Otherwise, the filler must perform this step.
Even more serious problems caused by the gap in the top perimeter of the inner body concern performance and perception. The gap in the perimeter tends to loosen the assembly between the inner body and the holder cup. This creates a degree of wobbliness of the holder cup and stick product as the holder cup is being raised and lowered, and even when the holder cup is in its fully extended position. This wobbliness makes it difficult to control the application of product to the application surface, while also conveying a low quality image to the consumer. We also note that generally, the secondary slot and perimeter gap of a conventional inner body are visible to a consumer, and the non-symmetrical aesthetic impact is negative. Some efforts may be made to obscure the gap in the top perimeter of the inner body, but these are not wholly effective, and just add another step to the manufacturing and/or assembly processes.
Unrealized up to now are the advantages of an inner body with no secondary slot at the top end, there being no breaks or gaps in the perimeter of the top of the inner body. These advantages include: the top of the inner body does not need to be held open with a tool; the holder cup does not need to be retracted before assembling the inner body and cam sleeve; the holder cup does not need to be extended before product filling; a manufacturer can supply a product filler with inner body/holder cup subassemblies that are ready to fill; the wobbliness in operation is reduced; any unsightly appearance may be hidden from view.
A main object of the present invention is to provide a container for a stick product that utilizes an inner body that has a continuous top perimeter, that is, one with no gaps in the top perimeter.
Another object of the invention is to provide improvements in methods of assembly of a container for a stick product.
A container (10) for a stick product (7) according to the present invention comprises a cap (1), a base (2), an A-shell (3), a cam sleeve (4), an inner body (5) and a holder cup (6). The inner body is continuous along the top perimeter, which means that the longitudinal slots of the inner body do not open up onto the top perimeter of the inner body. Significant advantages in assembly are realized. Containers according to the present invention may be useful for all types of stick products that are applied to a surface by drawing the product across a surface. These include lipsticks, lip balms, deodorant sticks, anti-perspirant sticks, glue sticks, etc.
Throughout the specification, the term “comprises” means that a collection of objects is not necessarily limited to those explicitly recited, but may or may not include additional objects.
For purposes of the present invention, a stick product is an elongated mass of solid or semi-solid product that is able to support its own weight when the elongated mass is suspended by one end.
Cap and Base
One embodiment of a base (2) is shown in
A-Shell and Cam Sleeve
Referring to
The side wall (4d) of the cam sleeve (4) is generally solid and has an outer surface (4e) and an inner surface (4f). The inner surface is provided with at least one helical groove, preferably with two helical grooves (4c, 4c′). The helical grooves start at the top (4b) of the cam sleeve and complete some number revolutions or fractions thereof, to end near the bottom (4a) of the cam sleeve. Also, the cam sleeve is able to receive the inner body (5) into itself, in a concentric fashion. When positioned around the inner body, the cam sleeve and inner body are able to rotate independently of each other.
Inner Body and Holder Cup
Referring to
A least one, preferably two longitudinal slots (5c, 5c′), 180° apart, pass through the side wall (5d) of the inner body (5). The upper and lower ends of the longitudinal slots may be formed as horizontal slot extensions (5e, 5e′). By design, neither the longitudinal nor the horizontal slots open up onto the top (5b) of the inner body, as is typically done. That is to say, there is no secondary slot, as discussed above. In fact, the perimeter of the top (5b) of the inner body is continuous or unbroken; this is critical. Also, the top of the inner body is formed to overhang (5k) the side wall (5d). During assembly, the inner body may be inserted into the cam sleeve (4) by pushing down on the overhang. The overhang has an inwardly beveled surface (5g) that slopes toward the interior of the inner body. This is different from the outwardly beveled surface commonly seen.
Above the level of the at least one longitudinal slot (5c, 5c′) of the inner body (5), at least one horizontal bead, preferably two horizontal beads (5f, 5f) extend along the side wall (5d). The diameter of the inner body at the level of the horizontal beads is slight greater than the diameter at the top (4b) of the cam sleeve (4), but less than the inner diameter of the A-shell (3). Therefore, as the bottom of the inner body is inserted into the top of the cam sleeve, the horizontal beads come to contact the top of the cam sleeve, which act as a stop to prevent further insertion of the inner body (see
Once the inner body is fully inserted into cam sleeve, it must be prevented from backing out. For example, when the base (2) is inserted into the bottom (5a) of the inner body, there will be some resistance which might dislodge the inner body with respect to the cam sleeve (4). To prevent this, a flexible tab (5j) is located in the side wall (5d), just below at least one of the longitudinal slots (5c, 5c′). The flexible tab is connected to the side wall of the inner body by a living hinge that biases the tab to protrude outward from the side wall. The flexible tab comprises a beveled side surface and a horizontal top surface. When the beveled surface of the tab hits the top (4b) of the cam sleeve, the tab flexes inwardly to allow the inner body to be inserted. But once the tab emerges from the bottom (4a) of the cam sleeve, the tab returns to its extended position, and the horizontal surface of the tab prevents upward movement of the inner body with respect to the cam sleeve. In the fully assembled container (10), the inner body protrudes from both ends of the cam sleeve, however, the top (5b) of the inner body does not protrude beyond the top (3b) of the A-shell (3).
Referring to
Alternatively, the plastic material at the top of the inner body (5) may be sufficiently flexible to allow the lugs (6c, 6c′) of the holder cup (6) to be forced through the top (5b) of the inner body, and into the longitudinal slots (5c, 5c′). Depending on the order of assembly, it is sometimes preferable that the inner body and cam sleeve (4) are capable of maintaining a partially assembled configuration prior to the insertion of the holder cup. Referring to
Several methods of assembly are possible, each with advantages. Examples of some of the preferred methods are described here.
1. Assemble the cam sleeve (4) at a predetermined height within the A-shell (3).
2. Partially insert the bottom (5a) of the inner body (5) into the cam sleeve so that the flexible tab (5j) of the inner body exerts an outward pressure against the inner surface (4f) of the cam sleeve, and the horizontal slot extensions (5e, 5e′) of the inner body remain exposed above the cam sleeve.
3. Assemble the holder cup (6) into the top (5b) of the inner body (5) such that the holder cup sits in an extended position, protruding from the top of the inner body, with the lugs (6c, 6c′) of the holder cup sitting in the horizontal slot extension (5e, 5e′) of the inner body.
4. Fully inserting the inner body into the cam sleeve by pushing down on the overhang (5k) of the inner body and simultaneously rotating the inner body until the horizontal beads (5f, 5f) of the inner body contact the top (4b) of the cam sleeve, at which point the flexible tab of the inner body extends outward below the bottom (4a) of the cam sleeve, the lugs of the holder cup enter the two helical grooves (4c, 4c′) of the cam sleeve, and the top (5b) of the inner body is below the top (3b) of the A-shell (3).
5. Insert the bottom (3a) of the A-shell and the bottom (5a) of the inner body into the base (2) such that the second set of gears (5i) of the inner body (5) are meshed with the first set of gears (2i) of the base (2).
6. Optionally, rotate the base with respect to the A-shell to lower the holder cup to its retracted position.
7. Optionally, a cap (1) is fitted onto the base to complete the container (10).
Variations of this method include the step of inserting a stick product (7) into the holder cup, this step occurring before step 3, or between steps 3 and 4, or between steps 4 and 5, or between steps 5 and 6.
1. Assemble the cam sleeve (4) at a predetermined height within the A-shell (3).
2. Assemble the inner body (5) and holder cup (6) such that the holder cup sits in its extended position, protruding from the top (5b) of the inner body, with the lugs (6c, 6c′) sitting in the horizontal slot extension (5e, 5e′).
3. Insert the bottom (5a) of the inner body into the top (4b) of the cam sleeve, and push down on the overhang (5k) of the inner body and simultaneously rotating the inner body until the horizontal beads (5f, 5f) of the inner body contact the top (4b) of the cam sleeve, and the flexible tab (5j) of the inner body extends outward below the bottom (4a) of the cam sleeve, while the lugs of the holder cup enter the two helical grooves (4c, 4c′) of the cam sleeve. At that point, the top (5b) of the inner body is below the top (3b) of the A-shell (3).
4. Insert the bottom (3a) of the A-shell and the bottom (5a) of the inner body into the base (2) such that the second set of gears (5i) of the inner body (5) are meshed with the first set of gears (2i) of the base (2).
5. Optionally, rotate the base with respect to the A-shell to lower the holder cup to its retracted position.
6. Optionally, a cap (1) is fitted onto the base to complete the container (10).
Variations of this method include the step of inserting a stick product (7) into the holder cup, this step occurring before step 1, or between steps 1 and 2, or between steps 2 and 3, or between steps 3 and 4, or between steps 4 and 5.
1. Partially insert the bottom (5a) of the inner body (5) into the cam sleeve (4) so that the flexible tab (5j) of the inner body exerts an outward pressure against the inner surface (4f) of the cam sleeve, and the horizontal slot extensions (5e, 5e′) of the inner body remain exposed above the cam sleeve.
2. Insert the holder cup (6) into the top (5b) of the inner body, so that the holder cup sits in its extended position, protruding from the top (5b) of the inner body, with the lugs (6c, 6c′) sitting in the horizontal slot extensions (5e, 5e′).
3. Fully inserting the inner body into the cam sleeve by pushing down on the overhang of the inner body and simultaneously rotating the inner body until the horizontal beads (5f, 5f) of the inner body contact the top (4b) of the cam sleeve, and the flexible tab (5j) of the inner body extends outward below the bottom (4a) of the cam sleeve, while the lugs (6c, 6c′) of the holder cup (6) enter the two helical grooves (4c, 4c′) of the cam sleeve.
4. Insert the cam sleeve (4) into the A-shell (3) to a pre-determined height such that the top (5b) of the inner body is below the top (3b) of the A-shell (3).
5. Insert the bottom (3a) of the A-shell and the bottom (5a) of the inner body into the base (2) such that the second set of gears (5i) of the inner body (5) are meshed with the first set of gears (2i) of the base (2).
6. Optionally, rotate the base with respect to the A-shell to lower the holder cup to its retracted position.
7. Optionally, a cap (1) is fitted onto the base to complete the container (10).
Variations of this method include the step of inserting a stick product (7) into the holder cup, this step occurring before step 1, or between steps 1 and 2 or between steps 2 and 3 or between steps 3 and 4 or between steps 4 and 5, or between steps 5 and 6.
A container for a stick product according to the present invention, which utilizes an inner body having no gaps in the perimeter at the top of the inner body, offers a number of advantages over conventional designs. For example, during the pre-assembly of the holder cup and inner body, the top of the inner body does not need to be “opened” with a tool, which makes the assembly process more efficient; the holder cup does not need to be retracted before assembling the inner body and cam sleeve; the holder cup may not need to be extended before product filling; a manufacturer can supply a product filler with inner body/holder cup subassemblies that are ready to fill. A container according to the present invention is more stable, since there is no or reduced wobbliness of the holder cup and stick product. Overall, the present design has an improved appearance, as there are no visible gaps or scratches.
Number | Name | Date | Kind |
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5649777 | Holloway | Jul 1997 | A |
11311092 | Yan | Apr 2022 | B1 |
11553778 | Trochel | Jan 2023 | B2 |
20070217857 | Ho | Sep 2007 | A1 |