US20120124759A1

US20120124759A1 - Oral Care Implement

Info

Publication number: US20120124759A1
Application number: US13/298,450
Authority: US
Inventors: Thomas Fritsch
Original assignee: Braun GmbH
Current assignee: Braun GmbH
Priority date: 2010-11-19
Filing date: 2011-11-17
Publication date: 2012-05-24
Also published as: CA2817680A1; MX2013005490A; EP2454967A1; CN103209612A; JP2013542832A; WO2012066513A1

Abstract

An oral care implement is disclosed. The oral care implement includes a housing; a carrier element mounted for movement relative to the housing; and a locking assembly for preventing separation of the carrier element from the housing. The locking assembly includes a first locking element being supported at the housing at a first support location and a second support location and engaging into a first aperture or recess of the carrier element. The first and second support location lie offset to a rotation axis (R) of the carrier element.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of European Patent Convention Application No. 10014790.9, filed Nov. 19, 2010, the substance of which is incorporated by reference in its entirety herein.

FIELD OF THE INVENTION

The present disclosure is directed to an oral care implement and in particular to an oral care implement that includes a housing and a carrier element mounted for movement relative to the housing.

BACKGROUND OF THE INVENTION

Oral care implements are known that have a carrier element mounted for movement relative to the housing, where the oral care implement may be a replacement brush head for an electric toothbrush and the carrier element may be a bristle carrier mounted for oscillating rotation. It is further known to secure the carrier element to the housing by using a locking pin that is supported at the housing and that engages into an aperture or recess in the carrier element in order to prevent that the movably supported carrier element can get separated from the housing in case a pull-off force act on the carrier element. The latter can happen in particular when the oral care implement is dropped to the floor or when a user jams the oral care implement into the user's mouth.
Thus it is a desire to provide an oral care implement having an improved locking of a movably mounted carrier element.

SUMMARY OF THE INVENTION

In one embodiment, an oral care implement is provided. The oral care implement includes a housing; a carrier element mounted for movement relative to the housing; and a locking assembly for preventing separation of the carrier element from the housing. The locking assembly includes a first locking element being supported at the housing at a first support location and a second support location and engaging into a first aperture or recess of the carrier element. The first and second support location lie offset to a rotation axis (R) of the carrier element.
In another embodiment, an oral care implement is provided. The oral care implement includes a housing; a carrier element mounted for movement relative to the housing; a locking assembly for preventing separation of the carrier element from the housing. The locking assembly includes a first locking element being supported at the housing at a first support location and engaging into a first aperture or recess of the carrier element. A second locking element, the first and second locking elements arranged for locking the carrier element and the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments set forth in the drawings are illustrative in nature and not intended to limit the invention defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

FIG. 1 is a depiction of an oral care device having an oral care implementd;

FIG. 2 is a depiction of a replaceable brush head for an electric toothbrush;

FIG. 3 is a longitudinal cut through a brush head as shown in FIG. 2 where a locking assembly includes a first locking element engaging into a first aperture or recess;

FIG. 4 is a longitudinal cut through another embodiment of a brush head in accordance with the present disclosure, where the locking assembly includes a first and a second locking element, where the second locking element is integral with a carrier element;

FIG. 5 is a longitudinal cut through the head section of a further embodiment of a brush head in accordance with the present disclosure, where the locking assembly includes a first and a second locking element, where the second locking element is realized as an extension of a metal axle to which a shaft element is mounted;

FIG. 6 is a top view onto the head section of an electric toothbrush that includes a carrier element that is movably mounted;

FIG. 7 is a cross sectional cut through a first embodiment of the brush head shown in FIG. 6 along plane A-A indicated in FIG. 6 where the locking assembly includes a first locking element;

FIG. 8 is a cross sectional cut through a further embodiment of the brush head shown in FIG. 6 along plane A-A indicated in FIG. 6 in accordance with the present disclosure, where the locking assembly includes a first and a second locking element;

FIG. 9A is a longitudinal cut through another embodiment of the brush head shown in FIG. 6 along plane B-B indicated in FIG. 6 in accordance with the present disclosure, where the locking assembly includes a first locking element that is supported at the housing at a first and a second support location;

FIG. 9B is a longitudinal cut through the brush head shown in FIG. 9A along plane D-D indicated in FIG. 9A.

DETAILED DESCRIPTION OF THE INVENTION

The following text sets forth a broad description of numerous different embodiments of the present disclosure. The description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. It will be understood that any feature, characteristic, component, composition, ingredient, product, step or methodology described herein can be deleted, combined with or substituted for, in whole or part, any other feature, characteristic, component, composition, ingredient, product, step or methodology described herein. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. All publications and patents cited herein are incorporated herein by reference.
According to the present disclosure, an oral care implement is proposed that has a housing, a carrier element mounted for movement relative to the housing, a locking assembly for preventing separation of the carrier element from the housing, wherein the locking assembly either has at least a first locking element that is supported at the housing at a first support location and a second support location and that engages into a first aperture or recess of the carrier element or at least a first locking element that is supported at the housing at a first support location and that engages into a first aperture or recess of the carrier element and a second locking element that is arranged for locking the carrier element and the housing.
In one embodiment, the oral care implement may be a replacement brush head for an electric toothbrush.
Oral care implements such as electric toothbrushes need to be in conformance with respective standards such as the communicated EN 60335-2-52/A11 (“Particular requirements for oral hygiene appliances”). According to this standard, an appliance needs to survive a fall from 700 mm height onto a hardwood board without damage (it is referred to the documents available for example, via CENELEC). In particular, the fall may apply a force onto movably mounted parts of the toothbrush, for example, movably mounted (bristle) carrier elements. These movably mounted parts may get separated from the toothbrush if the applied force is above a threshold pull-off force. It is known in the art to lock a movably arranged carrier element by a locking assembly comprising a locking element, for example, a metal pin that is press fitted into a bore in the brush head housing, which locking element further engages into an aperture or recess provided in the carrier. A fall from 700 mm may apply a force onto the carrier element such that the locking element is ripped out of the housing (i.e. the electric toothbrush gets damaged and the carrier element gets separated), in particular as a leverage force may act on the locking element. According to one aspect of the present disclosure, improvements are described that are intended to avoid or at least reduce the probability that such damages occur easily. Improved locking has also the further effect that a slowly acting threshold pull-off force, as may occur when for example, a user jams a tooth under the movably mounted carrier element will also not lead to easy separation of the carrier element from the housing.
As shown in the Figures, several embodiments of the proposed oral care implement are described. An oral care implement in accordance with the present disclosure may either be an oral care device such as an electric toothbrush or an oral care implement may be a replacement head for an oral care device such as a replacement brush head for an electric toothbrush.
FIG. 1 is a depiction of an exemplary embodiment of an oral care device shown as an electrical toothbrush having a handle 20 and a detachably arranged head section shown as a brush head 10. In the following, exemplary embodiments will be discussed where the oral care implement is a replaceable brush head of an electric toothbrush. This should not be interpreted to limit the scope of the present disclosure.
FIG. 2 is a depiction of an exemplary oral care implement as proposed shown as a replaceable brush head 10. The brush head 10 has an essentially tubular housing 101 to which at a distal end a movably arranged carrier element 102 is mounted. A bristle tuft field 200 is mounted to the carrier element 102, using mounting technology as is known in the art, for example, anchor tufting, AFT (anchor free tufting) or any other technology.
FIG. 3 shows a longitudinal cut through a brush head 10 as shown in FIG. 2. The brush head 10 has an essentially tubular housing 101 that extends in a longitudinal direction. The tubular housing 101 has an opening at a proximal side that is arranged so that a drive shaft of a handle section of an electrical toothbrush can be slid into the opening until a snap hook 163 of a shaft element 160 snaps into a groove of the drive shaft, as is known in the art. A carrier element 102 is movably mounted to the distal end of the brush head 10. The carrier element 102 is mounted on an axle 150 so that the carrier element 102 can rotate (or oscillate in a rotating manner) around rotation axis R defined by the axle 150. Carrier element 102 is mechanically coupled to the shaft element via a T-shaped coupling element 161 to transfer an oscillatory rotation of the drive shaft around the longitudinal axis via the shaft element 160 into an oscillatory rotation of the carrier element 102 around rotation axis R. The shaft element 160 is further mounted to the housing 101 with a mounting pin 162 that extends along the longitudinal direction. Here, the rotation axis R is essentially perpendicular to the longitudinal direction. In the shown embodiment, the carrier element 102 extends beyond the housing 101 in such a way that during regular operation, a force F could become applied at the carrier element 102 such that the carrier element 102 could become separated from the housing 101. The force at which the separation occurs is the threshold pull-off force. Such instances may in particular occur when the brush head 10 is dropped to the floor or when a user (for example, a child) jams a tooth between the carrier element 102 and the housing 101. In order to prevent that the carrier element 102 can get easily separated (and thus could be swallowed), a locking assembly is provided, which locking assembly may be a first locking element 110 that is supported at the housing 101 at a first support location 130 such that the first locking element 110 (shown in this embodiment as a metal locking pin having a broadened head, i.e. a mushroom head) is fixedly connected to the housing, for example. the first locking element 110 may be press-fitted into a bore in the housing 101. The first locking element 110 extends beyond the first support location and engages into a first aperture or recess 120 in the carrier element 102.
As discovered by the inventors, it is sensible to design the locking assembly in such a way that the threshold pull-off force is as high as possible so that the brush head is not damaged and/or the carrier element is not separated.
In FIG. 4 essentially the same longitudinal cut as in FIG. 3 is shown, but FIG. 4 shows one exemplary embodiment of a locking assembly according to the present disclosure that improves the locking assembly shown in FIG. 3. Elements essentially identical to element in FIG. 3 will not be described again and reference is made to the description relating to FIG. 3. Besides the first locking element 110 that was already described in detail with reference to FIG. 3, a second locking element 103 is provided. The second locking element 103 may be a locking element that is fixedly mounted at the carrier element 102A, in particular, the second locking element 103 may be an integral part of the carrier element 102A (for example, the second locking element 103 may be molded in the injection molding process of the carrier element). In another embodiment, the second locking element may be a metal pin that is press-fitted into a bore provided in the carrier element. The second locking element 103 extends into a recess or aperture 104 provided in the housing 101A. Here, the housing 101A provides the recess by its hollow inner part. The second locking element 103 just grips behind the housing wall. A force acting onto the carrier element 102A would not only have to overcome the locking strength of the first locking element 110 but also the locking strength of the second locking element 103.
FIG. 5 shows a further embodiment of a locking assembly provided in a brush head similar to the brush head shown in FIG. 3. The brush head shown in FIG. 5 includes as part of its locking assembly the first locking element 110 supported at a first support location 130 at the housing 101B that engages into a first aperture or recess 120 in the carrier element 102B as was discussed in detail with reference to FIG. 3. In addition, the locking assembly of the brush in accordance with FIG. 5 includes a second locking element 162A. In this embodiment, the second locking element 162A is integral with the mounting pin to mount the shaft element 160B at the housing 101B. In one embodiment, the second locking element 162A prolongs the mounting pin such that it on one end provides the mount for the shaft element 160B and on the second end engages into a second aperture or recess 125 formed in the carrier element 102B. The second locking element 162A (for example, a locking pin, in particular as a metal locking pin) is supported at a second support location 135 at the housing 101B.
FIG. 6 is a partial depiction of another embodiment of an oral care implement 1A. Here, the oral care implement may be an electric toothbrush that includes a handle section 20A (only partially shown) and a head section 10A, for example, a replaceable brush head. The replaceable brush head 10A includes a housing 101C that is—inter alia—attached to the housing 21 of the handle section 20A via a snap hook 104, which snap hook 104 has a snap nose that engages into a cutout 22 provided in the housing 21 of the handle section 20. The brush head 10A further includes a carrier element 102C mounted for oscillatory rotation similar to the carrier element 102 of the previous embodiments. The brush head 10A here also includes an additional carrier element 103A.
FIG. 7 is a cross sectional cut through the oral care implement 1A shown in FIG. 6 taken along plane A-A as indicated in FIG. 6. The carrier element 102C is mounted on an axle 150A for oscillatory rotation around rotation axis P. A locking assembly as provided in this embodiment includes, similar to the embodiment shown in FIG. 3, a first locking pin 111 that is supported at the housing 101C of the brush head at a first support location 131 and that engages into a first aperture or recess 121 formed in the carrier element 102C.
FIG. 8 is the same cross sectional cut as shown in FIG. 7 but of a different embodiment of the brush head in accordance with the present disclosure. As shown, the locking assembly includes a first locking element 111 supported at a first support location 131 at the housing 101D that engages into a first aperture or recess 121 formed in the carrier element 102D. In addition, the locking assembly includes a further locking element 112 supported at the housing 101D at a second support location 132 at the housing 101D that engages into a second aperture or recess 122 formed in the carrier element 102D. Here, the first and second support locations 131 and 132 are opposite to each other with respect to the carrier axis defined by the axle 150A, i.e. the angular distance of the two support locations with respect to the rotation axis is 180 degrees.
FIG. 9A is a longitudinal cut through another embodiment of an oral care implement as shown in FIG. 6 along plane B-B as indicated in FIG. 6. A carrier element 102E is movably mounted on an axle 150A for oscillatory rotation. A locking assembly is provided that in this embodiment includes a first locking element 113 that engages into a first aperture or recess 123 formed in the carrier element 102E. In FIG. 9B, which is a longitudinal cut through the same embodiment as shown in FIG. 9A but along plane D-D indicated in FIG. 9A, it is shown that the first locking element 113 is supported at the housing 101E at one end at a first support location 133 and at a second end at a second support location 134. In this embodiment, the double-sided support of the locking element 113 results in strong locking as the forces acting on the locking element 113 are absorbed by the two support locations and leverage force effects are effectively reduced. The first and second support location lie offset to the rotation axis of the carrier element 102E, so that the angular distance between the two support locations is around 110 degrees.
Utilizing the above described improved locking assemblies will also support making use of a soft plastic material for the housing. Choosing a relatively strong (and typically expensive) plastic material such as POM (polyoxymethylene), PBT (polybutylene terephthalate) or PA (polyamide) as material of the housing will result in a certain threshold pull-off force that is given by the details of the design (for example, wall thickness, shape of the locking elements, material of the locking elements etc.), but which also benefits from the strength of the plastic material. Choosing a softer plastic material such as ABS (acrylonitrile-butadiene-styrene), ASA (acrylonitrile-styrene-acrylate) or PP (polypropylene) will obviously result in a lower threshold pull-off force for the same design. Hence, using the improved locking assemblies together with soft plastic material as housing material will result in an increase of the threshold pull-off force in comparison to a single locking element or single support location, respectively, as shown for example in FIG. 3 or FIG. 7.
Further measures to improve the locking behavior of the locking assembly may include thickening the wall of the housing around the first and/or second support location or making use of reinforced plastic material (optionally only locally for example, for the support locations or for the second locking element that is integral with the carrier element).
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.”
Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

1. An oral care implement comprising:

a housing;

a carrier element mounted for movement relative to the housing; and

a locking assembly for preventing separation of the carrier element from the housing;

wherein the locking assembly includes a first locking element being supported at the housing at a first support location and a second support location and engaging into a first aperture or recess of the carrier element; and further wherein the first and second support location lie offset to a rotation axis (R) of the carrier element.

2. An oral care implement comprising:

a housing;

a carrier element mounted for movement relative to the housing;

wherein the locking assembly includes a first locking element being supported at the housing at a first support location and engaging into a first aperture or recess of the carrier element; and a second locking element, the first and second locking elements arranged for locking the carrier element and the housing.

3. The oral care implement according to claim 2, wherein the second locking element is supported at the housing at a second support location and engages either into the first aperture or recess or into a second aperture or recess.

4. The oral care implement according to claim 3, wherein the second locking element is an integral part of the carrier element and engages into the second aperture or recess provided at the housing.

5. The oral care implement according to claim 2, wherein the carrier element is mounted for rotational or oscillating rotational movement around a rotation axis (R), wherein the rotation axis is arranged perpendicular to a longitudinal direction of the oral care implement.

6. The oral care implement according to claim 5, wherein the first support location and the second support location are arranged at an angular distance of at least 30 degrees with respect to the rotation axis (R).

7. The oral care implement according to claim 2, wherein the material of the housing is selected from the group consisting of polypropylene, acrylonitrile-butadiene-styrene, and acrylonitrile-styrene-acrylate and has an E-module of below about 2500 N/mm².

8. The oral care implement according to claim 2, wherein the first locking element is realized as a metal pin.

9. The oral care implement according to claim 2, wherein the first locking element is fixedly supported at the housing.

10. The oral care implement according to claim 2, wherein the oral care implement exhibits a threshold pull-off force (F) of at least about 35 Newton.

11. The oral care implement according to claim 2, wherein the oral care implement exhibits a threshold pull-off force (F) of at least about 90 Newton.

12. The oral care implement according to claim 2, wherein the carrier element at least partly extends beyond the housing.

13. The oral care implement according to claim 2, wherein the first locking element is press fitted into the housing.

14. The oral care implement according to claim 2, wherein the housing is reinforced where the first locking element is supported at the housing.