CROSS REFERENCE TO RELATED APPLICATIONS

This applications claims benefit of U.S. Provisional Patent Application Serial No. 62/064177, Filed on October 15, 2014, the entirety of which is incorporated herein for reference;

TECHNICAL FIELD

The present disclosure relates to safety razor cartridges, and more specifically to razor cartridges that include a connector for attachment to a razor handle.

BACKGROUND Many modern wet shaving razors, also known as safety razors, comprise a handle and a razor cartridge mounted to the handle. Some razors are so-called disposable razors wherein the handle and razor cartridge together are disposed of after use. Other razors can be in the form of a so-called system that comprises a handle that can be reused and a removable razor cartridge that is disposed of after use and can be replaced with a new cartridge.

U.S. Patent number 5,787,586 discloses a shaving system having a razor cartridge including a housing carrying razor blades and a connector, also known as an interconnect member that pivotally supports the housing. A razor handle has an extension providing cartridge support structure that mates with a recess of the interconnect member. The interconnect member has detents that snap-fittingly engage depressions of the extension. The extension is provided with a user-operated ejector to eject or disconnect the razor cartridge.

SUMMARY The force a user must apply to the ejector button of the '586 safety razor to disconnect the cartridge has to be sufficient to effectively disengage the snap fits. As apparently disclosed in '586 the two sets of snap-fits of the respective detents and depressions are positioned (and thus intended) to disengage simultaneously. Disengagement of any one snap-fit is substantially effected by the wall bearing the detent flexing in a direction away from the extension by a distance sufficient to allow the detent to be released from its respective depression. The stiffness or rigidity of this wall is a function of the third power of its thickness, i.e. t ³ where t = wall thickness. During manufacture of interconnect members, one of skill would understand that slight dimensional variations will be present in both the thickness of the wall and in the height of the detents (in a direction perpendicular to the wall). The effect of these slight dimensional variations in wall thickness and height (the height of the detent affecting the distance the wall must flex to disengage the snap fit) can introduce a large and significant range of forces that a user must apply to the ejector button to disconnect different razor cartridges. This is further affected by the snap-fits disengaging simultaneously and thus the force to disengage any one snap-fit being exactly additive to the force required to disengage the other. This can be detrimental to the user's experience. The present disclosure has for its objective to eliminate, or at least substantially alleviate the limitations of the prior art by providing a safety razor comprising a handle and a razor cartridge. The handle has an extension providing cartridge support structure that mates with a recess of a razor cartridge. The extension defines an axis along which the razor cartridge is moveable during connection to, and disconnection from, the extension. The extension has a pair of depressions arranged symmetrically about the axis and each adapted to snap-fittingly receive a respective one of two detents of the razor cartridge. The handle includes a user-operable ejector, slidable along the extension and adapted to engage the razor cartridge to eject or disconnect the razor cartridge from the extension of the handle. The two detents of the razor cartridge extend into the recess and are asymmetric relative to the axis when the razor cartridge is connected to the handle. When the user operates the ejector to disconnect the razor cartridge from the extension, a first of the two detents engages an edge of the respective depression before a second of the two detents engages an edge of the respective depression. In this manner the snap-fits do not disengage simultaneously. The rate of increase of force a user must apply to an ejector button to disengage any one razor cartridge is reduced (compared to '586). The force range and magnitude a user must apply to the ejector to disengage different razor cartridges (that might exhibit slight dimensional variations as described above) is also thus reduced providing benefits to the user. In a further embodiment the razor cartridge includes a housing having one or more razor blades and an interconnect pivotally attached to the housing, the interconnect including the recess. In further embodiments of any embodiment or aspect provided above, the first detent is asymmetrically positioned along the axis relative to the second detent and/or any one of the two detents has a greater height and/or a greater lead angle than the other of the two detents.

In a further embodiment of any embodiment or aspect provided above, the pair of depressions are respectively positioned on one of a common outer surface of the extension and opposed outer surfaces of the extension.

These and other advantages of the present disclosure will be apparent to one of ordinary skill in the art in light of the following Detailed Description and Drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is made to the attached drawings, wherein elements having the same reference numeral designations represent like elements throughout, and wherein:

Fig. 1 is a front view of a safety razor;

Fig. 2 is a side view of the safety razor of Fig. 1 ;

Fig. 3 is a front view of the handle of the safety razor of Fig. 1;

Fig. 4 is a top end view of Fig. 3;

Fig. 5 is a partial sectional view of Fig. 3; Fig. 6 is a bottom end view of the interconnect of the razor cartridge of the safety razor of Fig. 1 ;

Fig. 7 is a partial sectional view of Fig. 6;

Fig. 8 is a schematic figure of the safety razor of Fig. 1 during disconnection of the razor cartridge; and

Fig. 9 is a schematic sectional view of portions of another safety razor.

DETAILED DESCRIPTION

Referring now to the drawings and in particular Figs. 1-2, a safety razor 10 is depicted. The safety razor 10 comprises a handle 12 having connected thereto a razor cartridge 14. In these Figs, and also Fig. 3 the handle 12 is shown foreshortened purely for the convenience of representing these Figs, at a suitable scale and the present disclosure is not limited in regard to the length or shape of the handle 12. The razor cartridge 14 comprises a housing 16 with one or more razor blades 18 mounted within the housing 16. The housing 16 is supported by an interconnect 20. In the depicted embodiment the housing 16 can be pivotally supported by the interconnect 20 such that the housing 16 can pivot relative to the interconnect 20 about pivot axis 24. In the depicted embodiment the housing 16 is supported by shell bearings 22 although the present disclosure should not be limited in this regard and other support methods such as pins in holes and so-called living hinges are within the scope of the present disclosure. The housing 16 can also be rigidly supported, e.g. integrally formed with the interconnect 20, for example as described in U.S. patent number 6,026,577, the content of which relating to an integral housing (described as head 11 therein) and interconnect (described as chamber 15 therein) is incorporated herein for reference.

Figs. 3-4 and 5 depict respectively a front view, a top end view and a partial sectional view of the handle 12. The handle 12 includes an extension 30 that mates with a recess 50 of the interconnect 20 (see Fig. 6). The extension 30 defines an axis 32 along which the razor cartridge 14 moves relative to the handle when it is connect to and disconnected from the handle 12. The extension 30 includes a pair of depressions 34 that are symmetrically arranged about axis 32. Both depressions 34 have a leading edge 36 as will be described later in the present disclosure. Handle 12 includes an ejector 40 that is slidable along the extension by a user operating a button 42. Ejector 40 can be U-shaped and distal ends 44 of each leg of the U are adapted to contact interior surfaces (see 52 in Fig. 6) of the interconnect 20 of the razor cartridge 14 when a user operates the button 42 to disconnect or otherwise eject the razor cartridge 14 from the handle 12.

In Fig. 6 a bottom end view of the interconnect 20 of the razor cartridge 14 of the safety razor 10 of Fig. 1 is depicted, i.e. a view of the entrance to the recess 50. Recess 50 includes interior surfaces 52 as described in the preceding paragraph. Recess 50 includes two detents 56, 58 extending into the recess 50 from interconnect side wall 60. Detents 56, 58 (as depicted) can have a different height "v" defined in a direction normal to the interior surface of wall 60 (see also Fig. 7). In Fig. 7, a partial sectional view of Fig. 6, the leading edge (right hand side as depicted) of detent 56 is offset relative along the axis of connection 32 to the leading edge of detent 58 by a distance "h." Detent 56 can have a lead angle "a" which can be different to the lead angle of detent 58. Fig. 8 is a schematic figure of the safety razor 10 of Fig. 1 during disconnection of the razor cartridge 14 and shows essentially a portion of Fig. 3 further including the detents 56, 58 (depicted solid black) positioned in their respective depressions 34. As can be seen, during disconnection, detent 56 engages the leading edge 36 of its depression 34 in advance of detent 58 engaging the leading edge 36 of its depression 34. In this manner the snap-fits of the detents within respective depressions do not disengage simultaneously.

In the embodiments of Figs 1-8 (especially as depicted in Figs. 3 and 8) the pair of depressions 34 are positioned on a common outer surface 38 of the extension 30. In Fig. 9 the pair of depressions 34 are positioned on opposed outer surfaces 62, 64 of extension 30 and symmetrically arranged about axis 32. In this embodiment, detents 72, 74 are correspondingly positioned such that a first of the two detents (72 or 74) engages an edge 36 of the respective depression 34 before a second of the two detents (74 or 72) engages an edge 36 of the respective depression 34 as the interconnect 20 is disconnected from the extension 30 (i.e. moved relatively left to right as depicted in Fig. 9).

Those skilled in the art will recognize that variations and modifications can be made without departing from the true scope of the disclosure as defined by the claims that follow. For example, the depressions can be provided in the interior wall of the recess and the detents provided on the outer surface(s) of the extension. The detents can be symmetrically arranged about the axis and the depressions can be asymmetric relative to the axis. The detents or depressions can be on adjacent outer surfaces of the extension, e.g. a top and a side surface. Features disclosed in connection with any one embodiment can be used alone or in combination with each feature of the respective other embodiments.