Patent Description:
A method of forming an oral care implement and a corresponding oral care implement according to the present invention are defined in the independent claims. Aspects useful for understanding the invention are described in the following. In one aspect, an oral care implement has a handle and a head coupled to the handle. The head may include a base that is coupled to the handle and a resilient bridge. The resilient bridge may be coupled to the base. The resilient bridge may be flexible between a normal state in which a portion of the resilient bridge is spaced from the base by a gap and a flexed state in which a portion of the resilient bridge is moved toward the base and into the gap. The resilient bridge may be self-biased into the normal state under flexure stress. Tooth cleaning elements may be coupled to the resilient bridge. Furthermore, the resilient bridge may include one or more apertures through which tooth cleaning elements that are fixed to the base may extend.

In one aspect, an oral care implement comprises: a handle; a head coupled to the handle and extending along a longitudinal axis, the head comprising: a base; a resilient bridge flexible between: (<NUM>) a normal state in which the resilient bridge comprises a bowed section that is bowed away from the base so that a gap exists between a lower surface of the resilient bridge and an upper surface of the base; and (<NUM>) a flexed state in which the bowed section of the resilient bridge is moved toward the base and into the gap; and the resilient bridge being self-biased into the normal state, and wherein in the normal state, the bowed section of the resilient bridge is under flexure stress; a plurality of movable tooth cleaning elements mounted to the
resilient bridge and extending from an upper surface of the resilient bridge; and a first fixed tooth cleaning element mounted to the base and having a free end, the first fixed tooth cleaning element extending through a first aperture in the resilient bridge.

In another aspect, an oral care implement comprises: a handle; a head coupled to the handle, the head comprising: a base; a resilient bridge coupled to the base and supported above the base, the resilient bridge flexible between: (<NUM>) a normal state in which a gap exists between a lower surface of the resilient bridge and an upper surface of the base; and (<NUM>) a flexed state in which a portion of the resilient bridge is moved toward the base and into the gap; a loop of movable tooth cleaning elements mounted to the portion of the resilient bridge and extending from an upper surface of the resilient bridge, the loop of movable tooth cleaning elements collectively defining a central cavity having a floor, a first aperture in the floor extending through the resilient bridge from the lower surface of the resilient bridge to the upper surface of the resilient bridge; and a first fixed tooth cleaning element mounted to the base and having a free end, the first fixed tooth cleaning element extending through the first aperture and into the central cavity.

In yet another aspect, an oral care implement comprises: a handle; a head coupled to the handle and extending along a longitudinal axis, the head comprising: a base having a proximal end coupled to a distal end of the handle and a distal end; a resilient bridge comprising: at least one carrier section; a curved portion having a convex outer surface, a concave inner surface, a lower end coupled to the distal end of the base and an upper end coupled to the at least one carrier section; a second end coupled to the distal end of the handle; the resilient bridge flexible between: (<NUM>) a normal state in which a gap exists between a lower surface of the resilient bridge and an upper surface of the base; and (<NUM>) a flexed state in which the curved portion is deformed such that a portion of the resilient bridge is moved toward the base and into the gap; and a plurality of movable tooth cleaning elements mounted to the at least one carrier section of the resilient bridge and extending from an upper surface of the resilient bridge.

In a further aspect, a method of forming an oral care implement comprises: a) providing a body comprising a base and a bridge extending from a distal end of the base, the bridge terminating in a free end; b) mounting a plurality of tooth cleaning elements to the bridge; c) bending the bridge toward a proximal end of the base; and d) coupling the free end of the bridge to a proximal end of the base, thereby forming a head of an oral care implement.

Relative terms such as "lower," "upper," "horizontal," "vertical," "above," "below," "up," "down," "top" and "bottom" as well as derivative thereof (e.g., "horizontally," "downwardly," "upwardly," etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion.

Referring first to <FIG> concurrently, an oral care implement <NUM> will be described in accordance with an embodiment of the present invention. In the exemplified embodiment, the oral care implement <NUM> is in the form of a manual toothbrush. However, in certain other embodiments the oral care implement <NUM> can take on other forms such as being a powered toothbrush, a tongue scraper, a gum and soft tissue cleanser, a water pick, an interdental device, a tooth polisher, a specially designed ansate implement having tooth engaging elements, or any other type of implement that is commonly used for oral care. Thus, it is to be understood that the inventive concepts discussed herein can be applied to any type of oral care implement unless a specific type of oral care implement is specified in the claims.

The oral care implement <NUM> generally comprises a handle <NUM> and a head <NUM>. The handle <NUM> extends from a proximal end <NUM> to a distal end <NUM>. The handle <NUM> is an elongated structure that provides the mechanism by which the user can hold and manipulate the oral care implement <NUM> during use. In the exemplified embodiment, the handle <NUM> is generically depicted having various contours for user comfort. Of course, the invention is not to be limited by the specific shape illustrated for the handle <NUM> in all embodiments and in certain other embodiments the handle <NUM> can take on a wide variety of shapes, contours, and configurations, none of which are limiting of the present invention unless so specified in the claims.

In the exemplified embodiment, the handle <NUM> is formed of a rigid plastic material, such as for example without limitation polymers and copolymers of ethylene, propylene, butadiene, vinyl compounds, and polyesters such as polyethylene terephthalate. Of course, materials other than those noted above can be used to form the handle <NUM>, including metal, wood, or any other desired material that has sufficient structural rigidity to permit a user to grip the handle <NUM> and manipulate the oral care implement <NUM> during toothbrushing. Although not illustrated in the exemplified embodiment, the handle <NUM> may also include a grip that is formed of a resilient/elastomeric material. Such a grip may be coupled to or molded over a portion of the handle <NUM> that is typically gripped by a user's thumb and forefinger during use and/or over portions of the handle that are typically gripped by a user's palm during use to increase comfort to a user.

The head <NUM> of the oral care implement <NUM> is coupled to the handle <NUM> and has a front surface <NUM> and an opposing rear surface <NUM>. The head <NUM> of the oral care implement <NUM> extends along a longitudinal axis A-A. In some embodiments the head <NUM> may be formed integrally with the handle <NUM> as a single unitary structure using a molding, milling, machining, or other suitable process. In other embodiments the handle <NUM> and the head <NUM> may be formed as separate components which are operably connected at a later stage of the manufacturing process by any suitable technique known in the art, including without limitation thermal or ultrasonic welding, a tight-fit assembly, a coupling sleeve, threaded engagement, adhesion, or fasteners. Thus, the head <NUM> may, in certain embodiments, be formed of any of the rigid plastic materials described above as being used for forming the handle <NUM>, although the invention is not to be so limited in all embodiments and other materials that are commonly used during toothbrush head manufacture may also be used.

The oral care implement <NUM> also comprises a plurality of tooth cleaning elements <NUM> extending from the front surface <NUM> of the head <NUM>. As will be discussed in more detail below, the plurality of tooth cleaning elements <NUM> comprise a plurality of movable tooth cleaning elements <NUM> and one or more fixed tooth cleaning elements <NUM>. Where it does not conflict with the disclosure below, the invention is not to be limited by the structure, pattern, orientation, and material of the tooth cleaning elements <NUM> in all embodiments. Furthermore, where it does not conflict with the other disclosure provided herein, it should be appreciated that the term "tooth cleaning elements" may be used in a generic sense to refer to any structure that can be used to clean, polish, or wipe the teeth and/or soft oral tissue (e.g. tongue, cheek, gums, etc.) through relative surface contact. Common examples of "tooth cleaning elements" include, without limitation, bristle tufts, filament bristles, fiber bristles, nylon bristles, polybutylene terephthalate (PBT) bristles, spiral bristles, rubber bristles, elastomeric protrusions, flexible polymer protrusions, combinations thereof, and/or structures containing such materials or combinations. Thus, any combination of these tooth cleaning elements may be used within the tooth cleaning elements <NUM> in some embodiments.

In embodiments that use elastomeric materials to form one or more of the tooth cleaning elements <NUM>, suitable elastomeric materials may include any biocompatible resilient material suitable for uses in an oral hygiene apparatus. To provide optimum comfort as well as cleaning benefits, the elastomeric material of any such tooth cleaning element may have a hardness property in the range of A10 to A70 Shore hardness in one embodiment, or A8 to A25 Shore hardness in another embodiment. One suitable elastomeric material is styrene-ethylene/butylene-styrene block copolymer (SEBS) manufactured by GLS Corporation. Nevertheless, SEBS material from other manufacturers or other materials within and outside the noted hardness range could be used.

The tooth cleaning elements <NUM> may be coupled to the head <NUM> in any manner known in the art, including staples, in-mold tufting (IMT), anchor-free tufting (AFT), or a modified AFT known as AMR. The details of using AFT as the tooth cleaning element coupling technique will be described in more detail below with reference to the exemplified embodiment and <FIG>.

Although not illustrated in the exemplified embodiment, the head <NUM> of the oral care implement <NUM> may include a soft tissue cleanser coupled to or positioned on the rear surface <NUM> of the head <NUM>. An example of one suitable tissue cleanser that may be used with the present invention and positioned on the rear surface <NUM> of the head <NUM> is disclosed in <CIT> to the assignee of the present application. Such a soft tissue cleanser may include protuberances, which can take the form of elongated ridges, nubs, or combinations thereof. Of course, in certain embodiments the oral care implement <NUM> may not include any soft tissue cleanser such as in the exemplified embodiment.

Still referring to <FIG> collectively, the head <NUM> of the oral care implement <NUM> will be further described. In the exemplified embodiment, the head <NUM> generally comprises a base <NUM> and a resilient bridge <NUM>. The resilient bridge <NUM> is coupled to the base <NUM> to form the head <NUM>. Specifically, the resilient bridge <NUM> is coupled to the base <NUM> and to the handle <NUM> in such a manner that a lower surface <NUM> of the resilient bridge <NUM> is spaced apart from an upper surface <NUM> of the base <NUM> by a gap <NUM>, as best illustrated in <FIG>. Although the phrase "coupled to" is used to describe the relationship between the resilient bridge <NUM> and the base <NUM>, as described herein in certain embodiments the resilient bridge <NUM> or portions thereof may be integrally formed with the base <NUM>. In the exemplified embodiment, the gap <NUM> forms a transverse passageway that extends through the head <NUM> from a first peripheral outer surface or first lateral surface <NUM> of the head <NUM> to a second peripheral outer surface or second lateral surface <NUM> of the head <NUM>, the second peripheral outer surface <NUM> being located opposite to the first peripheral outer surface <NUM>.

The base <NUM> extends from a proximal end <NUM> to a distal end <NUM>. Specifically, the proximal end <NUM> of the base <NUM> is coupled to the distal end <NUM> of the handle <NUM>. In the exemplified embodiment the base <NUM> of the head <NUM> is formed integrally with the handle <NUM> although the base <NUM> of the head <NUM> may be separately formed from and later connected to the handle <NUM> in other embodiments. The resilient bridge <NUM> of the head <NUM> extends from a first end <NUM> to a second end <NUM>. The first end <NUM> of the resilient bridge <NUM> is coupled to the distal end <NUM> of the base <NUM> and the second end <NUM> of the resilient bridge <NUM> is coupled to the distal end <NUM> of the handle <NUM>. As will be described in more detail below, in certain embodiments at least a portion of the resilient bridge <NUM> may be integrally formed with the handle <NUM> and the base <NUM> of the head <NUM>, although this is not required in all embodiments. Specifically, in certain embodiments the first end <NUM> of the resilient bridge <NUM> may be integrally formed with the distal end <NUM> of the base <NUM> and the second end <NUM> of the resilient bridge <NUM> may be coupled to the distal end <NUM> of the handle during the manufacturing process using mechanical means such as ultrasonic welding, adhesion, fasteners, or the like. This process will be described in more detail below with reference to <FIG>.

Referring to <FIG> concurrently, the relationship between and specific details of the base <NUM> and the resilient bridge <NUM> will be described in more detail. As noted above, the resilient bridge <NUM> is coupled to the base <NUM> in such a manner that the resilient bridge <NUM> and the base <NUM> are spaced apart by the gap <NUM>. The resilient bridge <NUM> comprises a U-shaped distal section <NUM>, a middle section <NUM>, and a proximal section <NUM>. The U-shaped distal section <NUM> of the resilient bridge <NUM> comprises the first end <NUM> of the resilient bridge <NUM> and defines a distal-most peripheral outer surface of the head <NUM> that is free of an overhang. Thus, the U-shaped distal section <NUM> of the resilient bridge <NUM> forms a U-shaped distal end of the head <NUM>.

Described another way, the U-shaped distal section <NUM> of the resilient bridge <NUM> may be referred to herein as a curved portion of the resilient bridge <NUM>. The curved portion or U-shaped distal section <NUM> of the resilient bridge <NUM> comprises a convex outer surface <NUM>, a concave inner surface <NUM>, a lower end <NUM> that is coupled to the distal end <NUM> of the base <NUM>, and an upper end <NUM> that is coupled to at least one carrier section (the carrier sections are described in more detail below and are denoted as reference numerals <NUM>-<NUM>) of the resilient carrier <NUM>. The concave inner surface <NUM> of the curved portion or U-shaped distal section <NUM> of the resilient bridge <NUM> faces the gap <NUM>. The convex outer surface <NUM> of the curved portion or U-shaped distal section <NUM> of the resilient bridge <NUM> forms or comprises the distal-most portion of the head <NUM>. The resilient bridge <NUM>, or the U-shaped distal section <NUM> (i.e., curved portion) thereof, forms the distal-most end of the head <NUM>. The U-shaped distal section <NUM> forms a hinge-like structure at the distal end of the head <NUM> between the carrier sections <NUM>-<NUM> of the resilient bridge <NUM> and the base <NUM>.

As noted above, the movable tooth cleaning elements <NUM> are coupled to the resilient bridge <NUM>. The movable tooth cleaning elements <NUM> are referred to herein as being movable because, as will be discussed in more detail below with specific reference to <FIG> and <FIG>, the resilient bridge <NUM> is movable, which in turn renders the movable tooth cleaning elements <NUM> movable by virtue of their being coupled to the resilient bridge <NUM>. The resilient bridge <NUM> comprises a first carrier section <NUM>, a second carrier section <NUM>, and a third carrier section <NUM>. In certain embodiments the first carrier section <NUM> may be referred to herein as a distal-most carrier section and the third carrier section <NUM> may be referred to herein as a proximal-most carrier section.

The first carrier section <NUM> is coupled the upper end <NUM> of the U-shaped distal section or curved section <NUM> of the resilient bridge <NUM> and to a first end <NUM> of the second carrier section <NUM> via a first flexible transverse hinge <NUM>. The third carrier section <NUM> is coupled to a second end <NUM> of the second carrier section <NUM> via a second flexible transverse hinge <NUM>. The second end <NUM> of the second carrier section <NUM> is opposite the first end <NUM> of the second carrier section <NUM> in the direction of the longitudinal axis A-A of the head <NUM>. In the exemplified embodiment, a first group of the movable tooth cleaning elements 116a are mounted to the first carrier section <NUM>, a second group of the movable tooth cleaning elements 116b are mounted to the second carrier section <NUM>, and a third group of the movable tooth cleaning elements 116c are mounted to the third carrier section <NUM>. In the exemplified embodiment, a lower surface of each of the first carrier section <NUM>, the second carrier section <NUM>, and the third carrier section <NUM> is spaced apart from the upper surface <NUM> of the base <NUM> by the gap <NUM>. Stated another way, the gap <NUM> extends beneath the entirety of each of the first, second, and third carrier sections <NUM>, <NUM>, <NUM>. Although the exemplified embodiment includes three separate carrier sections <NUM>-<NUM>, the invention is not to be so limited and in other embodiments the resilient bridge <NUM> may include only two separate carrier sections or more than three separate carrier sections as desired.

As can be seen in particular in <FIG>, each of the first and second flexible transverse hinges <NUM>, <NUM> spans across an entirety of a width of the resilient bridge <NUM>. The first and second flexible transverse hinges <NUM>, <NUM> may be formed by connecting the first, second, and third carrier sections <NUM>, <NUM>, <NUM> with a thin strut of a rigid material that is encased within a resilient material such as a thermoplastic elastomer. Thus, each of the first and second flexible transverse hinges <NUM>, <NUM> may comprise the thin strut and the surrounding elastomeric material. The first flexible transverse hinge <NUM> permits the first and second carrier sections <NUM>, <NUM> to flex and move relative to one another and the second flexible transverse hinge <NUM> permits the second and third carrier sections <NUM>, <NUM> to flex and move relative to one another. The transverse hinges <NUM>, <NUM> also permit the entire resilient bridge <NUM> to move upwardly and downwardly relative to the base <NUM> of the head <NUM>. Thus, the flexibility provided by the transverse hinges <NUM>, <NUM> facilitates movement or flexibility of the resilient bridge <NUM> between a normal state as illustrated in <FIG> and a flexed state as illustrated in <FIG>, the details of which will be described in more detail below.

The base <NUM> of the head <NUM> comprises an aperture <NUM> that extends entirely through the base <NUM> from the upper surface <NUM> of the base <NUM> to the rear surface <NUM> of the head <NUM> (which is formed by a lower surface or rear surface of the base <NUM>). The aperture <NUM> provides an additional degree of flexibility into the base <NUM> of the head <NUM> so that the head <NUM> can better adapt to the contours of a user's mouth during oral hygiene activities using the oral care implement <NUM>. The aperture <NUM> may also enhance hygiene of the oral care implement <NUM> by permitting bacteria and other debris collected onto the head <NUM> of the oral care implement <NUM> during use to be washed away via the aperture <NUM>. In the exemplified embodiment the aperture <NUM> is elongated along a width of the head <NUM> but may be positioned and arranged in manners that are other than those depicted in the exemplified embodiment. The aperture <NUM> may also be omitted in some embodiments.

Furthermore, as noted above the plurality of tooth cleaning elements <NUM> includes one or more fixed tooth cleaning elements <NUM>. In the exemplified embodiment the fixed tooth cleaning elements <NUM> includes a first fixed tooth cleaning element 117a and a second fixed tooth cleaning element 117b. Each of the first and second fixed tooth cleaning elements 117a, 117b is mounted to the base <NUM>. The first and second fixed tooth cleaning elements 117a, 117b are referred to as fixed because they are non-movable relative to the base <NUM> from which they extend. Each of the first and second fixed tooth cleaning elements 117a, 117b extends from the base <NUM> to a terminal end or free end <NUM>. In the exemplified embodiment, the first and second fixed tooth cleaning elements 117a, 117b are coupled to the base <NUM> such that a bottom portion <NUM> of the first and second fixed tooth cleaning elements 117a, 117b are exposed on the rear surface <NUM> of the head <NUM>. Of course, this is not required in all embodiments.

Furthermore, in the exemplified embodiment each of the first and second fixed tooth cleaning elements 117a, 117b may be an interdental element having a transverse cross-sectional area that tapers moving from the base <NUM> toward the free end <NUM> of the first and second fixed tooth cleaning elements 117a, 117b. Thus, the first and second fixed tooth cleaning elements 117a, 117b may facilitate cleaning the interproximal areas of a user's oral cavity. In the exemplified embodiment, the fixed tooth cleaning elements 117a, 117b have a rectangular cross-sectional shape and they taper to form a somewhat elongated free end <NUM>. Of course, the invention is not limited to the cross-sectional shape illustrated in all embodiments and the fixed tooth cleaning elements 117a, 117b may be conical, cylindrical, or the like in other embodiments. Each of the first and second fixed tooth cleaning elements 117a, 117b may be formed of a thermoplastic elastomer, a rigid plastic material, wood, a single tuft of bristles, or the like as may be desired. Rubber or a thermoplastic elastomer may be a desirable material to ensure that the first and second fixed tooth cleaning elements 117a, 117b can flex and move during conventional toothbrushing and can penetrate the interproximal regions to effectively remove plaque therefrom.

In the exemplified embodiment, the first and second fixed tooth cleaning elements 117a, 117b are located on the longitudinal axis A-A of the head <NUM> and are spaced apart from one another. Of course, the invention is not to be so limited in all embodiments and the first and second fixed tooth cleaning elements 117a, 117b may be located offset from the longitudinal axis A-A of the head <NUM> in other embodiments. Furthermore, although in the exemplified embodiment there are two of the fixed tooth cleaning elements 117a, 117b illustrated, in other embodiments a single fixed tooth cleaning element <NUM> or more than two fixed tooth cleaning elements <NUM> may be provided.

In the exemplified embodiment, a first aperture <NUM> is formed into the first flexible transverse hinge <NUM> of the resilient bridge <NUM> located between the first and second carriers <NUM>, <NUM> of the resilient bridge <NUM>. Furthermore, in the exemplified embodiment a second aperture <NUM> is formed into the second flexible transverse hinge <NUM> of the resilient bridge <NUM> located between the second and third carriers <NUM>, <NUM>. In the exemplified embodiment, the first aperture <NUM> is located between the first and second carriers <NUM>, <NUM> and the second aperture <NUM> is located between the second and third carriers <NUM>, <NUM>. Stated another way, the first aperture <NUM> is located between the first group of movable tooth cleaning elements coupled to the first carrier <NUM> and the second group of movable tooth cleaning elements coupled to the second carrier <NUM>. The second aperture <NUM> is located between the second group of movable cleaning elements coupled to the second carrier <NUM> and the third group of movable cleaning elements coupled to the third carrier <NUM>.

Although the first and second apertures <NUM>, <NUM> are exemplified as being formed into the first and second flexible transverse hinges <NUM>, <NUM>, the invention is not to be so limited in all embodiments. The first and second apertures <NUM>, <NUM> may alternatively be located within the first, second, and or third carriers <NUM>, <NUM>, <NUM> of the resilient bridge <NUM> if so desired. Thus, the first and second apertures <NUM>, <NUM> may merely be formed into the resilient bridge <NUM> in some embodiments. The first and second apertures <NUM>, <NUM> extend entirely through the resilient bridge <NUM> from the lower surface <NUM> of the resilient bridge <NUM> to the front surface <NUM> of the head <NUM> (which also forms an upper surface <NUM> of the resilient bridge <NUM>).

Regardless of the specific location of the first and second apertures <NUM>, <NUM>, the first and second apertures <NUM>, <NUM> are positioned to be aligned with the first and second fixed tooth cleaning elements 117a, 117b so that the first and second fixed tooth cleaning elements 117a, 117b extend through the first and second apertures <NUM>, <NUM>, respectively. Specifically, the first fixed tooth cleaning element 117a extends from the base <NUM> and through the gap <NUM> in a direction towards the resilient bridge <NUM>. The first fixed tooth cleaning element 117a then extends through the first aperture <NUM> formed into the resilient bridge <NUM> (and specifically formed into the first flexible transverse hinge <NUM> in the exemplified embodiment). Similarly, the second fixed tooth cleaning element 117b extends from the base <NUM> and through the gap <NUM> in a direction towards the resilient bridge <NUM>. The second fixed tooth cleaning element 117b then extends through the second aperture <NUM> formed into the resilient bridge <NUM> (and specifically formed into the second flexible transverse hinge <NUM> in the exemplified embodiment). It should be appreciated that in some embodiments the first and second fixed tooth cleaning elements 117a, 117b and/or the first and second apertures <NUM>, <NUM> may be omitted.

In the exemplified embodiment, the first aperture <NUM> has an elongated oval transverse cross-sectional shape such that the first aperture <NUM> has a width that is two to four times greater than a width of the first fixed tooth cleaning element 117a (the widths being measured in a direction transverse to the longitudinal axis A-A). The first aperture <NUM> also has a length that is approximately one to three times greater than a length of the first fixed tooth cleaning element 117a (the lengths being measured along or in the direction of the longitudinal axis A-A). Forming the first aperture <NUM> to be larger than the first fixed tooth cleaning element 117a provides additional space within the first aperture <NUM> for the first fixed tooth cleaning element 117a to extend through such that the first fixed tooth cleaning element 117a can still extend through the first aperture <NUM> even if it becomes bent, splayed, or the like over time.

Furthermore, as noted above the resilient bridge <NUM> is flexible such that it can move towards and away from the base <NUM> into the gap <NUM> during use (described in more detail below). By sizing and shaping the first aperture <NUM> relative to the first fixed tooth cleaning element 117a as described herein and illustrated in the drawings, the first fixed tooth cleaning element 117a will remain extending through the first aperture <NUM> even if the resilient bridge <NUM> is tilted or angled relative to the base <NUM> during use. Although the relationship between the first aperture <NUM> and the first fixed tooth cleaning element 117a is described in detail herein, it should be appreciated that the same relationship exists between the second aperture <NUM> and the second fixed tooth cleaning element 117b.

Referring briefly to <FIG>, although the pattern and arrangement of the movable tooth cleaning elements <NUM> is not to be limiting of the present invention in all embodiments, in certain embodiments the movable tooth cleaning elements <NUM> comprises a loop <NUM> of the movable tooth cleaning elements <NUM>. The loop <NUM> is formed by a plurality of the movable cleaning elements <NUM> that are arranged in a ring or loop about an axis. In the exemplified embodiment the loop <NUM> is oval-shaped, but the loop may be circular in other embodiments. Alternatively, the loop <NUM> may be a square or other shape. Regardless, the loop <NUM> forms a noticeable ring about an axis. The loop <NUM> defines a central cavity <NUM> having a floor <NUM>. In the exemplified embodiment, the first aperture <NUM> is formed into and located on the floor <NUM> of the central cavity <NUM>. Thus, the first fixed tooth cleaning element 117a extends through the first aperture <NUM> and into the central cavity <NUM> of the loop <NUM>. Thus, the loop <NUM> surrounds the aperture <NUM> and the first fixed tooth cleaning element 117a. A similar loop <NUM> surrounds the aperture <NUM> and the second fixed tooth cleaning element 117b.

In the exemplified embodiment, the loop <NUM> is formed by two arcuate cleaning elements located on the first carrier section <NUM> and two arcuate cleaning elements located on the second carrier section <NUM>. Specifically, the two arcuate cleaning elements located on the first carrier section <NUM> have arcuate surfaces that face the second carrier section <NUM> and the two arcuate cleaning elements located on the second carrier section <NUM> have arcuate surfaces that face the first carrier section <NUM>. Of course, the loop <NUM> may be entirely located on one of the first, second, and third carrier sections <NUM>, <NUM>, <NUM> in other embodiments, particularly in embodiments that have the aperture <NUM> located on one of the respective carrier sections.

Referring to <FIG> and <FIG> concurrently, the movement or flexibility of the resilient bridge <NUM> will be described. As noted above, the resilient bridge <NUM> is flexible between: (<NUM>) a normal state, illustrated in <FIG>, in which the resilient bridge <NUM> comprises a bowed section <NUM> that is bowed away from the base <NUM> so that the gap <NUM> exists between the lower surface <NUM> of the resilient bridge <NUM> and the upper surface <NUM> of the base <NUM>; and (<NUM>) a flexed state, illustrated in <FIG>, in which the bowed section <NUM> of the resilient bridge <NUM> is moved downwardly into the gap <NUM> and towards the base <NUM>. The resilient bridge <NUM> is self-biased into the normal state such that without any external forces being applied to the resilient bridge <NUM>, the resilient bridge <NUM> will be in the normal state illustrated in <FIG>. Furthermore, in the normal state, the bowed section <NUM> of the resilient bridge <NUM> is under flexure stress. Specifically, the bowed section <NUM> of the resilient bridge <NUM> is bowed in the normal state due to the manner in which the resilient bridge <NUM> is folded about the base <NUM> and coupled to the handle <NUM>. The movable tooth cleaning elements <NUM> are movable due to their attachment to the resilient bridge <NUM> which is movable as described herein. The resilient bridge <NUM> flexes into the flexed state upon application of a force F onto the resilient bridge <NUM> in the direction of the base <NUM> that is sufficient to overcome the self-biasing force of the resilient bridge <NUM>.

In the exemplified embodiment, when the resilient bridge <NUM> is in the normal state, the lower surface <NUM> of the resilient bridge <NUM> is concave in the longitudinal direction and the upper surface <NUM> of the resilient bridge <NUM> is convex in the longitudinal direction. Furthermore, in the exemplified embodiment when the resilient bridge <NUM> is in the flexed state, the lower surface <NUM> of the resilient bridge <NUM> is convex in the longitudinal direction and the upper surface <NUM> of the resilient bridge is concave in the longitudinal direction. Of course, the invention is not to be limited as such in all embodiments. Furthermore, although the upper and lower surfaces <NUM>, <NUM> of the resilient bridge <NUM> are concave and convex in the longitudinal direction, in certain embodiments the upper and lower surfaces <NUM>, <NUM> of the resilient bridge is planar along any transverse plane taken through the resilient bridge <NUM>.

When the resilient bridge <NUM> is in the normal state, the gap <NUM> has a first maximum gap height HG1 measured between the upper surface <NUM> of the base <NUM> and the lower surface <NUM> of the resilient bridge <NUM>. When the resilient bridge <NUM> is in the flexed state, the gap <NUM> has a second maximum gap height HG2 measured between the upper surface <NUM> of the base <NUM> and the lower surface <NUM> of the resilient bridge <NUM>. The first maximum gap height HG1 is greater than the second maximum gap height HG2. In the exemplified embodiment, the gap <NUM> still exists when the resilient bridge <NUM> is in the flexed state, although it is smaller than when the resilient bridge <NUM> is in the normal state. In some embodiments the gap <NUM>, or a portion thereof, may be eliminated when the resilient bridge <NUM> is in the flexed state such that the lower surface <NUM> of the resilient bridge <NUM> (or a portion thereof) may be in direct surface contact with the upper surface <NUM> of the base <NUM>.

Still referring to <FIG> and <FIG>, when the resilient bridge <NUM> is in the normal state, the free end <NUM> of the first fixed tooth cleaning element 117a is located a first height H1 above the upper surface <NUM> of the resilient bridge <NUM>. When the resilient bridge <NUM> is in the flexed state, the free end <NUM> of the first fixed tooth cleaning element 117a is located a second height H2 above the upper surface <NUM> of the resilient bridge <NUM>. As can be seen in a comparison of <FIG> and <FIG>, the second height H2 is greater than the first height H1. This occurs due to the resilient bridge <NUM> moving downwardly towards the base <NUM> when transitioning between the normal and flexed states and due to the first fixed tooth cleaning element 117a not moving when the resilient bridge <NUM> moves due to their being coupled directly to the base <NUM>.

Similarly, when the resilient bridge <NUM> is in the normal state, the free end <NUM> of the second fixed tooth cleaning element 117b is located a fourth height H4 above the upper surface <NUM> of the resilient bridge <NUM>. When the resilient bridge <NUM> is in the flexed state, the free end <NUM> of the second fixed tooth cleaning element 117b is located a fifth height H5 above the upper surface <NUM> of the resilient bridge <NUM>. As can be seen in a comparison of <FIG> and <FIG>, the fifth height H5 is greater than the fourth height H4. Furthermore, in the exemplified embodiment a tallest one of the plurality of movable bristles <NUM> has a third height H3 measured from the upper surface <NUM> of the resilient bridge to a free end of the tallest one of the plurality of movable bristles <NUM>. In the exemplified embodiment the first and fourth heights H1, H4 are less than the third height H3 and the second and fifth heights H2, H5 are greater than the third height H3.

Furthermore, in the exemplified embodiment the loop <NUM> has a sixth height H6 measured from the upper surface <NUM> of the resilient bridge to a free end of the loop <NUM>. The sixth height H6 of the loop <NUM> is greater than the first height H1 of the first fixed tooth cleaning element 117a (and also the fourth height H4 of the second fixed tooth cleaning element 117b) and the sixth height H6 of the loop <NUM> is less than the second height H2 of the first fixed tooth cleaning element 117b (and also the fifth height H5 of the second fixed tooth cleaning element 117b). Thus, when the resilient bridge <NUM> is in the normal state, the loop is taller than the first and second fixed tooth cleaning elements 117a, 117b. When the resilient bridge <NUM> is in the flexed state, the loop is shorter than the first and second fixed tooth cleaning elements 117a, 117b. This occurs as a result of the resilient bridge <NUM>, and also the cleaning elements coupled thereto which includes the tooth cleaning elements that form the loop <NUM>, moving downwardly towards the base <NUM> as the resilient bridge <NUM> flexes from the normal state to the flexed state.

Still referring to <FIG> and <FIG>, in the exemplified embodiment the resilient bridge <NUM> is a multi-component plate structure. Specifically, the resilient bridge <NUM> comprises a first component <NUM> formed of a first material and a second component <NUM> formed of a second material, the first and second materials being different. In the exemplified embodiment, the first component <NUM> is formed integrally with the base <NUM> of the head <NUM> (and also with the handle <NUM>). Thus, in certain embodiments the first component <NUM> and the base <NUM> of the head <NUM> may be integrally formed via an injection molding process. The first component <NUM> and the base <NUM> may, in certain embodiments, be a rigid plastic material such as for example without limitation polymers and copolymers of ethylene, propylene, butadiene, vinyl compounds, and polyesters such as polyethylene terephthalate. The second component <NUM> may be a softer or more flexible material such as a thermoplastic elastomer or other rubber-like material. The second component <NUM> may be injection molded onto the first component <NUM> in a separate injection molding process as described herein below. The first component <NUM> may be sufficiently thin to permit the resilient bridge <NUM> to be bent to form the U-shaped distal section <NUM>. The bending of the resilient bridge <NUM> will be described in more detail directly below with regard to the method of forming the oral care implement and with reference to <FIG>.

Referring now to <FIG>, a method of forming the oral care implement <NUM> will be described. Referring first to <FIG>, in a first step a body <NUM> (which forms the head <NUM> of the oral care implement <NUM>) comprising the base <NUM> and a first portion <NUM> of the resilient bridge <NUM> is formed. The first portion <NUM> of the resilient bridge <NUM> may comprise or be formed of the first component <NUM> described above. Thus, in this embodiment the base <NUM> and the first portion <NUM> of the resilient bridge <NUM> are integrally formed as a monolithic structure. Furthermore, in certain embodiments the entire handle <NUM> may also be formed integrally with the first portion <NUM> of the resilient bridge <NUM> and the base <NUM> as a monolithic structure. Specifically, the body <NUM> is a monolithic structure that may comprise the base <NUM> and the first portion <NUM> of the resilient bridge <NUM> and may also comprise the handle <NUM>.

The first end <NUM> of the first portion <NUM> of the resilient bridge <NUM> extends from the distal end <NUM> of the base <NUM>. The first portion <NUM> of the resilient bridge <NUM> terminates in a free end, which is the second end <NUM> of the resilient bridge <NUM> as described above. The body <NUM> may be formed via a first injection molding step in a first mold cavity. Specifically, a molten plastic material may be injected into a first mold cavity having the shape of the body <NUM> to thereby form the body <NUM>. Thus, as described earlier, the base <NUM> and the resilient bridge <NUM>, or at least the first portion <NUM> of the resilient bridge <NUM>, may be formed integrally in a single mold cavity. Of course, the invention is not to be so limited in all embodiments and in other embodiments the base <NUM> and the first portion <NUM> of the resilient bridge <NUM> may be formed as separate elements in separate injection molding or other process and then later coupled together using techniques readily available to persons skilled in the art. However, for ease of manufacturing and reducing costs, forming the base <NUM> and the first portion <NUM> of the resilient bridge <NUM> as a monolithic structure may be desirable.

The base <NUM> at this stage of formation includes the aperture <NUM> as well as first and second cleaning element holes <NUM>, <NUM>. The first and second cleaning element holes <NUM>, <NUM> are the holes into which the first and second fixed tooth cleaning elements 117a, 117b are mounted to couple the first and second fixed tooth cleaning elements 117a, 117b to the base <NUM>, as described below with reference to <FIG>. In the exemplified embodiment, the first and second cleaning element holes <NUM>, <NUM> are positioned on opposing sides of the aperture <NUM> in the direction of the longitudinal axis A-A of the head <NUM>. The base <NUM> also includes a recess <NUM> formed into the upper surface <NUM> of the base <NUM> that provides a region on the base <NUM> for attachment of the second end <NUM> of the resilient bridge <NUM>. This recess <NUM> may be formed into the handle <NUM> instead of the base <NUM> in other embodiments.

The resilient bridge <NUM> includes the first, second, and third carriers <NUM>, <NUM>, <NUM>. Furthermore, the first and second apertures <NUM>, <NUM> are formed into the resilient bridge <NUM> and located between the first and second carriers <NUM>, <NUM> and the second and third carriers <NUM>, <NUM>, respectively.

Referring to <FIG>, in the next step of the formation process, the movable tooth cleaning elements <NUM> are coupled to the first, second, and third carriers <NUM>-<NUM> of the resilient bridge <NUM> by inserting the movable cleaning elements <NUM> into tuft holes (not illustrated) formed into the carriers <NUM>-<NUM>. In certain embodiments, this is accomplished via an AFT technique as described above, whereby the movable tooth cleaning elements <NUM> are inserted into openings in the first, second, and third carriers <NUM>-<NUM> and then heat is applied to the bottoms of the movable tooth cleaning elements <NUM> to form a melt matte that couples the movable tooth cleaning elements <NUM> to the first, second, and third carriers <NUM>-<NUM>. The melt matte prevents the movable tooth cleaning elements <NUM> from being pulled back through the tuft holes in the carriers <NUM>-<NUM>. Alternatively, the movable tooth cleaning elements <NUM> may be coupled to the resilient bridge <NUM> using staple technology or any of the other technologies listed herein above.

Referring to <FIG>, after the movable tooth cleaning elements <NUM> are coupled to the resilient bridge <NUM>, the body may be positioned in a second mold cavity whereby a second injection molding process takes place to form the structure illustrated in <FIG>. Of course, in some embodiments the second injection molding process may take place before the movable tooth cleaning elements <NUM> are coupled to the resilient bridge <NUM>. In the second injection molding process, a second molten plastic is injection molded such that the second component <NUM> of the resilient bridge <NUM> is molded atop of the first component <NUM> of the resilient bridge <NUM>. The second component <NUM> of the resilient bridge <NUM> may form a second portion <NUM> of the resilient bridge <NUM>. The second component <NUM> in the exemplified embodiment covers the melt matte of the movable tooth cleaning elements <NUM> to fixedly secure the movable tooth cleaning elements <NUM>, to the first, second, and third carriers <NUM>-<NUM>.

Furthermore, <FIG> illustrates the first and second fixed tooth cleaning elements 117a, 117b mounted within the first and second cleaning elements holes <NUM>, <NUM> of the base <NUM>. The first and second fixed tooth cleaning elements 117a, 117b may be molded into the first and second cleaning element holes <NUM>, <NUM> directly. Of course, the invention is not to be limited to forming the first and second fixed tooth cleaning elements 117a, 117b via injection molding directly into the holes <NUM>, <NUM>. In some embodiments, the first and second fixed tooth cleaning elements 117a, 117b may be formed separately from the body <NUM> and then affixed to the base <NUM> of the body <NUM> by inserting the fixed tooth cleaning elements 117a, 117b into the holes <NUM>, <NUM>. In such an embodiment, the first and second fixed tooth cleaning elements 117a, 117b may be fixed to the base <NUM> of the body <NUM> either via mechanical means (interference fit, tight fit, fasteners, adhesion, etc.) or via the injection molding described herein above. Furthermore, it should be appreciated that in some embodiments the first and second fixed tooth cleaning elements 117a, 117b may not be mounted to the base <NUM> until after the resilient bridge <NUM> is bent/folded over the base <NUM> as illustrated in <FIG> and discussed below.

Referring to <FIG>, in order to form the head <NUM>, the resilient bridge <NUM> is bent towards a proximal end of the base <NUM> and towards the handle <NUM>. Specifically, the terminal end <NUM> of the resilient bridge <NUM> is pulled in a clockwise direction towards the proximal end of the base <NUM>. State another way, the resilient bridge <NUM> is folded over the base <NUM> about the first end <NUM> of the resilient bridge <NUM>, which ends up forming the distal-most end of the head <NUM>. Specifically, the bending of the resilient bridge <NUM> causes the first end <NUM> of the resilient bridge <NUM> to bend into the U-shaped distal section <NUM> of the resilient bridge <NUM>.

Referring to <FIG>, the resilient bridge <NUM> continues to be bent until the first and second fixed tooth cleaning elements 117a, 117b extend through the first and second apertures <NUM>, <NUM>, respectively and until a connection feature <NUM> adjacent the second end <NUM> of the resilient bridge <NUM> enters into the recess <NUM>. Once in this position, the connection feature <NUM> may be ultrasonically welded or otherwise (adhesion, fasteners, tight fit, threaded engagement, or the like) fixedly coupled to the base <NUM> within the recess <NUM>. Thus, the final step in the process of forming the oral care implement <NUM> is coupling the free end <NUM> of the resilient bridge <NUM> to a proximal end of the base <NUM>, which thereby forms the head <NUM> of the oral care implement <NUM>. As discussed in detail below, upon completion of formation of the head <NUM> of the oral care implement <NUM>, the gap <NUM> exists between the lower surface <NUM> of the resilient bridge <NUM> and the upper surface <NUM> of the base <NUM>, and the resilient bridge <NUM> is under flexure stress.

Referring briefly to <FIG> concurrently, another embodiment of an oral care implement <NUM> will be described. The oral care implement <NUM> is similar to the oral care implement <NUM> and thus similar numbering will be used except that the <NUM>-series of numbers will be used. Certain features that are in both the oral care implements <NUM>, <NUM> will not be described with reference to the oral care implement <NUM> in the interest of brevity, it being understood that the description of the oral care implement <NUM> set forth above is applicable.

The oral care implement <NUM> generally comprises a handle <NUM> and a head <NUM>. The head comprises a base <NUM> and a resilient bridge <NUM>. A plurality of fixed tooth cleaning elements <NUM> are coupled directly to the base <NUM>. In this embodiment, the resilient bridge <NUM> is formed completely separately from the base <NUM> and is later coupled thereto. Thus, as exemplified, the resilient bridge <NUM> is in the form of a head plate that is coupled to the base <NUM>. A plurality of movable tooth cleaning element <NUM> are mounted to and extend from the resilient bridge <NUM>.

The resilient bridge <NUM> may be coupled to the base <NUM> using techniques known in the art, including without limitation welding (ultrasonic or otherwise), adhesion, fasteners, interference fit, or the like. In the exemplified embodiment, the resilient bridge <NUM> is welded to the base <NUM> to fixedly couple the resilient bridge <NUM> to the base <NUM>.

Referring to <FIG> and <FIG> concurrently, when the resilient bridge <NUM> is coupled to the base <NUM>, a gap <NUM> is formed between the lower surface of the resilient bridge <NUM> and the upper surface of the base <NUM>. Furthermore, when the resilient bridge <NUM> is coupled to the base <NUM>, the fixed tooth cleaning elements <NUM> extend through openings in the resilient bridge <NUM>. The resilient bridge <NUM> is adjustable or flexible between a normal state, illustrated in <FIG>, and a flexed state, illustrated in <FIG>. The resilient bridge <NUM> may be biased into the normal state. In the flexed state, upon application of a force onto the resilient bridge <NUM>, a portion of the resilient bridge <NUM> flexes into the gap <NUM> towards the base <NUM>. Thus, the fixed tooth cleaning elements <NUM> extend further from an upper surface of the resilient bridge <NUM> when the resilient bridge <NUM> is in the flexed state than when the resilient bridge <NUM> is in the normal state.

Referring again to <FIG>, in this embodiment the movable tooth cleaning elements <NUM> form at least three different loops 270a, 270b, 270c along the longitudinal axis of the head <NUM>. Each of the loops 270a, 270b, 270c defines a cavity, and each of the fixed tooth cleaning elements <NUM> extends into the cavity of one of the loops 270a, 270b, 270c. The central loop 270b extends a greater height from the resilient bridge <NUM> than the outer loops 270a, 270c. In certain embodiments, the fixed tooth cleaning elements <NUM> within the outer loops 270a, 270c may extend a greater height than the outer loops 270a, 270c within which they are positioned when the resilient bridge <NUM> is in the normal state and the fixed tooth cleaning element <NUM> within the central loop 270b may extend a height less than the central loop 270b within which it is positioned when the resilient bridge <NUM> is in the normal state. Forming the central loop 270b to be taller than the other tooth cleaning elements may be desirable in that the force of brushing will be applied to the central loop 270b, thereby effectively facilitating the flexing action of the resilient bridge <NUM>.

Referring to <FIG>, an oral care implement <NUM> will be described in accordance with an embodiment of the present invention. The oral care implement <NUM> is generally identical to the oral care implement <NUM> except as described herein below. Therefore, in the interest of brevity it will be understood that the description of the oral care implement <NUM> (and the oral care implement <NUM> where applicable) above is also applicable to the oral care implement <NUM>. Similar numbering will be used except that the <NUM>-series of numbers will be used. It should be appreciated that for numbers used and not described in <FIG>, the description of the similar feature with the similar numeral on the oral care implements <NUM>, <NUM> applies.

In this embodiment, the only difference between the oral care implement <NUM> relative to the oral care implement <NUM> is the manner in which the resilient bridge <NUM> is coupled to the base <NUM>. Specifically, in this embodiment the resilient bridge <NUM> has apertures <NUM>, <NUM> on its opposing first and second ends. Furthermore, the base <NUM> has protuberances <NUM>, <NUM> on its opposing first and second (or proximal and distal) ends. The resilient bridge <NUM> is coupled to the base <NUM> by inserting the protuberances <NUM>, <NUM> of the base <NUM> into a respective one of the apertures <NUM>, <NUM> in the resilient bridge <NUM>. Of course, the protuberances could be on the resilient bridge <NUM> and the apertures could be on the base <NUM> in an alternative embodiment. Thus, this exemplifies one embodiment in which the resilient bridge <NUM> is separately formed from the base <NUM> and the two components may be mechanically coupled together.

Claim 1:
A method of forming an oral care implement comprising:
a) providing a body (<NUM>) comprising a base (<NUM>) and a bridge (<NUM>) extending from a distal end (<NUM>) of the base (<NUM>), the bridge (<NUM>) terminating in a free end (<NUM>), the bridge (<NUM>) further comprising first and second carrier sections (<NUM>, <NUM>), the first and second carrier sections (<NUM>, <NUM>) separated by a first flexible transverse hinge (<NUM>), wherein a first aperture (<NUM>) is formed into the first flexible transverse hinge (<NUM>);
b) mounting a first group of movable tooth cleaning elements (116a) to the first carrier section (<NUM>) and a second group of movable tooth cleaning elements (116b) to the second carrier section (<NUM>);
c) mounting a fixed cleaning element (117a) to the base (<NUM>);
d) bending the bridge (<NUM>) toward a proximal end (<NUM>) of the base (<NUM>) so that the fixed cleaning element (117a) extends through the first aperture (<NUM>); and
e) coupling the free end (<NUM>) of the bridge (<NUM>) to the proximal end (<NUM>) of the base (<NUM>), thereby forming a head (<NUM>) of an oral care implement.