# Patent

## Title
Pivoting razors

## Abstract

Replaceable shaving assemblies are disclosed that include a blade unit, an interface element configured to removably connect the blade unit to a handle, on which the blade unit is pivotably mounted, and an elastomeric element disposed between the blade unit and interface element. Shaving systems including such shaving assemblies are also disclosed, as are methods of using such shaving systems.

## Background
RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 13/929,644, filed Jun. 27, 2013, which claims priority of U.S. Provisional Application Ser. No. 61/675,930, filed on Jul. 26, 2012. The complete disclosure of these applications are hereby incorporated by reference herein.


BACKGROUND
The invention relates to shaving systems having handles and replaceable blade units. Shaving systems often consist of a handle and a replaceable blade unit in which one or more blades are mounted in a plastic housing. After the blades in a blade unit have become dull from use, the blade unit is discarded, and replaced on the handle with a new blade unit. Such systems often include a pivoting attachment between the blade unit and handle, which includes a pusher and follower configured to provide resistance during shaving and return the blade unit to a “rest” position when it is not in contact with the user's skin.
SUMMARY
Embodiments of the present invention generally provide a reusable shaving system including a replaceable shaving assembly having a pivoting blade unit, and a reusable handle on which the shaving assembly is removably mounted.
In one aspect, the invention features a replaceable shaving assembly that includes a blade unit; a handle interface element configured to removably connect the blade unit to a handle, on which the blade unit is pivotably mounted; and an elastomeric element disposed between the blade unit and handle interface element.
Some implementations include one or more of the following features.
The handle interface element may include one or more protrusions, and the elastomeric element comprises at least one loop configured to receive the protrusion(s). For example, the handle interface element may include a pair of fingers extending in opposite directions, and the elastomeric element may include a pair of loops that are configured to receive the fingers. The loops may extend from the blade unit, or alternatively may be provided by mounting the elastomeric element onto the blade unit. For example, the elastomeric element may be provided on a blade unit interface element that clips onto the blade unit. In some cases, the blade unit includes an elastomeric guard and the loops are formed integrally with the guard. For example, the guard can include a pair of openings defining elongated elastomeric portions that initially lie flat against the cartridge, and, when stretched during assembly, form the loops.
In some preferred implementations, the elastomeric element is configured to bias the blade unit towards a rest position with respect to a pivot axis that is generally parallel to a long axis of the blade unit.
In another aspect, the invention features a shaving system that includes a handle having a distal end and a proximal end; and a replaceable shaving assembly that includes a blade unit, an interface element configured to removably connect the blade unit to a handle, on which the blade unit is pivotably mounted, and an elastomeric element disposed between the blade unit and interface element.
The shaving system may include any of the features disclosed above or elsewhere herein.
In yet a further aspect, the invention features a method of shaving comprising contacting the skin with the blade unit of a shaving system comprising a handle having a distal end and a proximal end, and a replaceable shaving assembly that includes a blade unit, an interface element configured to removably connect the blade unit to a handle, on which the blade unit is pivotably mounted, and an elastomeric element disposed between the blade unit and interface element.
Advantageously, in some implementations the elastomeric elements of the shaving systems disclosed herein eliminate the need for a “pusher/follower” razor construction to provide a force to supply resistance during shaving and return the blade unit to a “rest” portion when not in contact with the user's skin.



DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the shaving system according to one embodiment of the invention.
FIG. 2 is a perspective view of the shaving system of FIG. 1 viewed from a different angle.
FIG. 3 is an exploded view of the shaving system of FIG. 1.
FIG. 4 is a partially exploded view of the shaving system of FIG. 1 with the elastomeric portion assembled onto the blade unit.
FIG. 5 is a perspective view of the blade unit with the elastomeric portion attached.
FIG. 6 is a perspective view of a replaceable shaving assembly including the blade unit, elastomeric portion, and interface element.
FIG. 7 is a perspective view of a shaving system according to an alternate embodiment of the invention.
FIG. 8 is a perspective view of a replaceable shaving assembly including the blade unit, elastomeric portion, and interface element of the razor of FIG. 7.
FIG. 9 is a perspective view of the shaving assembly of FIG. 8 viewed from a different angle.
FIG. 10 is a perspective view of the blade unit and elastomeric portion of the razor of FIG. 7.
FIG. 11 is a top view of an alternate embodiment the shaving system.
FIG. 12 is a top view of the shaving system of FIG. 11 viewed without the handle.
FIG. 13 is a front view of the shaving system of FIG. 11.
FIG. 14 is a perspective view of the shaving system of FIG. 11 viewed without the handle.
FIG. 15 is a perspective view of the blade unit interface element.
FIG. 16 is a perspective view of the blade unit and interface element with the blade unit interface element omitted.
FIG. 17 is an exploded view of the blade unit, interface element, and the blade unit interface element.
FIG. 18 is an exploded view of the blade unit, interface element and the blade unit interface element taken from a different angle.
FIGS. 19-19A are perspective views of an embodiment in which the shaving assembly is designed to be permanently attached to the handle.



DETAILED DESCRIPTION
The present disclosure relates generally to consumer products and, in particular, to shaving systems with interchangeable blade units. In one embodiment, the present disclosure features a reusable consumer product system having an interchangeable pivoting blade unit, which includes an elastomeric return element.
FIG. 1 shows a shaving system 10 that includes a handle 12, handle interface element 14, and blade unit 16. Blade unit 16 is pivotably mounted on interface element 14 by the positioning of a pair of fingers 18, which extend from the interface element, in receiving bores 20 which may be molded integrally with the blade unit 16 or part of a separate connector snapped onto the blade unit. Pivoting of the blade unit is about an axis that is generally parallel to the long axis of the blade unit and is generally positioned to allow the blade unit to follow the contours of a user's skin during shaving. Generally, the handle interface element 14 and blade unit 16 are sold to the consumer as an integrated replaceable shaving assembly.
A pair of elastomeric loops 22, extending from a guard portion 21 of the blade unit 16, are positioned around the arms 24 from which fingers 18 extend. The elastomeric material of these loops is put under tension as the blade unit pivots during shaving. This tension provides resistance during shaving, limiting the free pivoting of the blade unit about the pivot axis described above, and providing a return force that biases the blade unit towards its rest position. Thus, the elastomeric loops provide the resistance and return that are typically provided by a pusher/follower assembly. The loops may be integrally molded with the guard, as shown in the figures (see, e.g., FIG. 2), may be comolded with the guard (e.g., the guard and loops may be of two different materials that are molded together), or may be attached to the guard.
The elastomeric loops can be formed, for example, from synthetic or natural rubber materials. Preferably, the elastomeric loops are formed from the same material as the guard. Suitable guard materials are well known in the shaving system art, and include, for example, polyether-based thermoplastic elastomers (TPEs) available from Kraiburg HTP, polyether-based thermoplastic vulcanizate elastomer (TPVs) available from GLS PolyOne Corporation under the tradename SantopreneTM. The elastomeric material is selected to provide a desired degree of restoring force and durability.
Preferably, the loops are positioned relatively close to the pivot point of the blade unit, so as to minimize strain on the elastomer and thus extend the shelf life and use life of the shaving assembly.
An exploded view of the shaving system is shown in FIG. 3, illustrating the guard/elastomeric loops separated from the blade unit housing and more clearly showing the arms and fingers of the interface element. In this view, indentations 25 in arms 24 are clearly visible. These indentations serve to hold the loops 22 securely in place after they have been threaded over the arms.
FIG. 4 shows the guard with loops 22 assembled onto the blade unit housing, prior to the arms and fingers of the interface element being threaded through the loops, while FIG. 5 shows an enlarged, detail view of the blade unit, showing the generally rectangular shape of the openings 23 in loops 22. FIG. 6 shows the replaceable shaving assembly, including the blade unit and interface element, as it would be viewed when attaching the shaving assembly to a handle.
FIGS. 7-10 show a shaving system 110 according to an alternate embodiment. In this embodiment, the loops 122 are thinner, in the form of a narrow web of material. In this embodiment, the arms 124 may include a pair of indentations, as shown, to better capture the thin loops.
The loops 122 can be formed, for example, by providing a guard 121 (FIG. 10) having a pair of elongated openings 130 which define webs 132. These webs lie flat against the blade unit housing as molded, but can be stretched to form loops 122 during assembly of the shaving assembly 110.
FIGS. 11-18 show a shaving system 210 according to another alternate embodiment. In this embodiment, the elastomeric material 222 is attached to the blade unit interface element 228. The blade unit interface element 228 attaches to the blade unit 16 by utilizing protrusions 290 (FIG. 15) which are configured to interface with blade unit receiving bores 300 (FIG. 17).
The handle interface element 14 is configured to snap onto the blade unit interface element 228 during replacement of the shaving assembly. Referring to FIGS. 5, 16, and 17, two fingers 224 protrude from the handle interface element 14 and have curved surfaces 280, which clip into receiving bores on the blade unit 16. This interaction allows the blade unit 16 to articulate with respect the handle 12 along an axis that is generally perpendicular to the long axis of the handle.
In this alternate embodiment, the elastomeric material 222 can be co-molded with or attached to the blade unit interface element 228. The elastomeric material 222 extends over the handle interface protrusions 224 so that some tension is generated within the elastomeric material. This tension provides for proper resistive force necessary for shaving in the same manner discussed above with regard to the embodiments shown in FIGS. 1-10.
In all of the embodiments discussed above, the elastomeric element is designed such that its geometry provides an applied load as assembled that is sufficient to overcome the friction of the system at rest (pretensioned load), typically at least 5 grams, e.g., 5 to 40 grams, and a load during shaving of from about 30 to 110 grams.
Also, while removable shaving assemblies have been discussed above, in some implementations the shaving system is designed to be disposable as a whole. In these cases, the shaving assembly is affixed to the handle in a manner that is not intended for the consumer to remove, e.g., by fixedly mounting the interface element on the distal end of the handle. This may be accomplished, for example, by engagement of corresponding mechanical locking features on the handle and interface element, by welding (e.g., ultrasonic welding), by molding the interface element integrally with the handle, or by any other desired mounting technique. An example of a disposable shaving system 400 is shown in FIG. 19, and the shaving assembly for such a system is shown in FIG. 19A. In this case, the handle 412 includes protrusions 450 (only one of which is shown, the other being on the opposite side of the handle), and the interface element includes corresponding locking indentations 452.
A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure.
For example, the blade unit interface element could clip or snap onto the blade unit in any desired manner.
Moreover, the openings in loops 22 may have any desired shape that will receive corresponding features on the handle interface element.
In addition, while only one embodiment was shown configured to be disposable, any of the previously mentioned embodiments could also be configured to be disposable as well.
Accordingly, other embodiments are within the scope of the following claims.

## Claims

1. A shaving assembly comprising:
a blade unit including an elastomeric guard;
a handle interface element configured to connect the blade unit to a handle, the blade unit being pivotably mounted on the handle interface element; and
an elastomeric element disposed between the blade unit and the handle interface element;
wherein the handle interface element includes a pair of fingers extending in opposite directions, and the elastomeric element comprises a pair of loops that are formed integrally with the guard and are configured to receive the fingers.

2. The shaving assembly of claim 1 wherein the fingers extend in opposite directions.

3. The shaving assembly of claim 1 wherein the guard includes a pair of openings defining elongated elastomeric portions that, when stretched during assembly, form the loops.

4. The shaving assembly of claim 3 wherein the elongated elastomeric portions are generally planar until stretched.

5. The shaving assembly of claim 1, wherein the elastomeric element is configured to bias the blade unit towards a rest position with respect to a pivot axis that is generally parallel to a long axis of the blade unit.

6. The shaving assembly of claim 1, wherein the elastomeric element comprises a thermoplastic elastomer.

7. The shaving assembly of claim 1, wherein the loops extend from the blade unit.

8. The shaving assembly of claim 1 further comprising a blade unit interface element interposed between the handle interface unit and the blade unit.

9. The shaving assembly of claim 8 wherein the elastomeric element is carried by the blade interface unit.

10. The shaving assembly of claim 8 wherein the blade interface element snaps onto the blade unit.

11. A shaving system comprising:
a handle having a distal end and a proximal end; and
a shaving assembly that includes a blade unit including an elastomeric guard, a handle interface element, the blade unit being pivotably mounted on the handle interface element, and an elastomeric element disposed between the blade unit and the handle interface element;
wherein the handle interface element includes a pair of fingers extending in opposite directions, and the elastomeric element comprises a pair of loops that are formed integrally with the guard and are configured to receive the fingers.

12. The shaving system of claim 11 wherein the fingers extend in opposite directions.

13. The shaving system of claim 11 wherein the guard includes a pair of openings defining elongated elastomeric portions that, when stretched during assembly, form the loops.

14. The shaving system of claim 13 wherein the elongated elastomeric portions are generally planar until stretched.

15. The shaving system of claim 11, wherein the elastomeric element is configured to bias the blade unit towards a rest position with respect to a pivot axis that is generally parallel to a long axis of the blade unit.

16. The shaving system of claim 11, wherein the elastomeric element comprises a thermoplastic elastomer.

17. The shaving system of claim 11, wherein the loops extend from the blade unit.

18. The shaving system of claim 11 further comprising a blade unit interface element interposed between the handle interface unit and the blade unit.

19. The shaving system of claim 18 wherein the elastomeric element is carried by the blade interface unit.

20. The shaving system of claim 18 wherein the blade interface element snaps onto the blade unit.

21. A method of shaving comprising contacting the skin with the blade unit of a shaving system comprising a handle having a distal end and a proximal end, and a shaving assembly that includes:
a blade unit including an elastomeric guard;
an interface element configured to connect the blade unit to a handle, the blade unit being pivotably mounted on the handle interface element; and
an elastomeric element disposed between the blade unit and the handle interface element;
wherein the handle interface element includes a pair of fingers extending in opposite directions, and the elastomeric element comprises a pair of loops that are formed integrally with the guard and are configured to receive the fingers.