Oral care implement having flexible handle

An oral care implement having a flexible handle. In one embodiment, the invention can be an oral care implement comprising: a head; and a handle extending along a longitudinal axis and connected to the head, the handle comprising: a main body integrally formed of a rigid material, the main body comprising a rigid gripping section terminating in a bulbous body, a rigid neck section terminating in a basin, and a flexible strut having a first end connected to the bulbous body and a second end connected to a floor of the basin; a resilient material encasing the flexible strut; and the flexible strut and the resilient material forming a hinge about which the rigid neck section pivots relative to the rigid gripping section upon a force being applied to the head.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present application is a U.S. national stage entry under 35 U.S.C. §371 of Patent Cooperation Treaty Patent Application No. PCT/US2012/30114, filed Mar. 22, 2012, the entirety of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to oral care implements, and specifically to oral care implements, such as toothbrushes, having flexible handles.

BACKGROUND OF THE INVENTION

Toothbrushes that incorporate flexibility into the handle and/or the head are known in the art. Such flexibility can be used to deter a toothbrush user from exerting too great of a force on the user's teeth during toothbrushing. Conventional toothbrushes that offer flexibility are often formed from multiple components that are mechanically coupled together. Due to the requirement to form such toothbrushes from multiple components, manufacturing costs are increased. Furthermore, in conventional toothbrushes that offer flexibility, the amount of flexibility is either limited due to the shape of the components or breakage occurs when the toothbrush is flexed beyond a certain point. Thus, a need exists for an improved toothbrush having a flexible handle.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to an oral care implement. In one aspect, the oral care implement can include a handle and a head. The handle can be formed of a rigid gripping section, a rigid neck section and a hinge section extending between and connecting the rigid gripping section to the rigid neck section. The hinge section can include a flexible strut. In some embodiments, a resilient material encases the flexible strut of the hinge section.

In one embodiment, the invention can be an oral care implement comprising: a handle extending along a longitudinal axis and comprising a rigid gripping section, a rigid neck section, and a hinge flexibly connecting the rigid neck section to the rigid gripping section, wherein one of the rigid neck section or the rigid gripping section comprises a bulbous body and the other one of the rigid neck section or the rigid gripping section comprises a basin; the hinge comprising: the bulbous body; the basin; a longitudinal strut of rigid material, the longitudinal strut having a first end connected to the bulbous body and a second end connected to a floor of the basin so that a separation gap exists between the bulbous body and the floor of the basin; and a resilient material in the separation gap; and a head connected to the rigid neck section of the handle.

In another embodiment, the invention can be an oral care implement comprising: a head; and a handle extending along a longitudinal axis and connected to the head, the handle comprising: a main body integrally formed of a rigid material, the main body comprising a first rigid longitudinal section terminating in a bulbous body, a second rigid longitudinal section terminating in a basin, and a longitudinal strut having a first end connected to the bulbous body and a second end connected to a floor of the basin; a resilient material encasing the flexible strut; and the longitudinal strut and the resilient material forming a hinge about which the second rigid longitudinal section pivots relative to the first rigid longitudinal section upon a force being applied to the head.

In yet another embodiment, the invention can be an oral care implement comprising: a head comprising a front surface and a rear surface; a plurality of teeth cleaning elements extending from the head; a handle connected to the head, the handle extending along a longitudinal axis and comprising a first rigid longitudinal section, a second rigid longitudinal section, and a hinge about which the second longitudinal section pivots relative to the first longitudinal section upon a force being applied to the head; the hinge comprising: a bulbous body of the first rigid longitudinal section; a basin of the second rigid longitudinal section, the basin formed by first and second longitudinal flanges that extend axially from a floor of the basin, the first and second longitudinal flanges being circumferentially spaced apart from one another by a first valley circumferentially aligned with a rear surface of the head; and a resilient material in a separation gap between the bulbous body and the floor of the basin that connects the first and second rigid longitudinal sections together.

In a further embodiment, the invention can be an oral care implement comprising: a head; a handle extending along a longitudinal axis and connected to the head, the handle comprising: a main body integrally formed of a rigid material, the main body comprising a rigid gripping section terminating in a first transverse shoulder, a rigid neck section terminating in a second transverse shoulder, and a longitudinal strut having a first end connected to the first transverse shoulder and a second end connected to the second transverse shoulder; a separation gap between the rigid gripping section and the rigid neck section; a first flexure limiting block protruding from the first transverse shoulder into the separation gap; a second flexure limiting block protruding from the second transverse shoulder into the separation gap, the first and second flexure limiting blocks circumferentially aligned with one another and a rear surface of the head so that a flexure limiting gap is formed between the first and second flexure limiting blocks; and a resilient material in the separation gap and in the flexure limiting gap; and the longitudinal strut and the resilient material forming a hinge about which the rigid neck section pivots relative to the rigid gripping section upon a force being applied to the head.

In a still further embodiment, the invention can be an oral care implement comprising: a head; a handle extending along a longitudinal axis and connected to the head, the handle comprising: a main body integrally formed of a rigid material, the main body comprising a rigid gripping section terminating in a first transverse shoulder, a rigid neck section terminating in a second transverse shoulder, a first strut, and a second strut oriented obliquely to the first strut; a separation gap between the rigid neck section and the rigid gripping section’ a resilient material in the separation gap; and the first strut, the second strut, and the resilient material forming a hinge pivotably coupling the rigid neck section and the rigid gripping section together.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1-3concurrently, an oral care implement100is illustrated in accordance with an embodiment of the present invention. In the exemplified embodiment, the oral care implement100is in the form of a manual toothbrush. However, in certain other embodiments the oral care implement100can take on other forms such as being a powered toothbrush, a flossing device, a tongue scraper, a gum and soft tissue cleaner, 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 implement100generally comprises a handle110and a head190. The head190comprises a front surface192and an opposing rear surface193and a plurality of tooth cleaning elements191extending from the head190beyond the front surface192. In the exemplified embodiment, the tooth cleaning elements191are generically illustrated. The exact number, size and configuration of the tooth cleaning elements191are not to be limiting of the present invention unless so specified in the claims. The tooth cleaning elements191can be particularly suited for brushing teeth, or can be particularly suited to polish teeth instead of or in addition to cleaning teeth. Although not illustrated, a tissue cleanser in the form of nubs or protrusions could be positioned on and protrude beyond the rear surface193of the head190.

As used herein, the term “tooth cleaning elements” is 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, spiral bristles, rubber bristles, elastomeric protrusions, flexible polymer protrusions, combinations thereof and/or structures containing such materials or combinations. Suitable elastomeric materials 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 the tooth or soft tissue engaging elements has a hardness property in the range of A8 to A25 Shore hardness. 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 elements191of the present invention can be connected to the head190in any manner known in the art. For example, staples/anchors, in-mold tufting (IMT) or anchor free tufting (AFT) could be used to mount the cleaning elements/tooth engaging elements. In AFT, a plate or membrane is secured to the brush head such as by ultrasonic welding. The bristles extend through the plate or membrane. The free ends of the bristles on one side of the plate or membrane perform the cleaning function. The ends of the bristles on the other side of the plate or membrane are melted together by heat to be anchored in place. Any suitable form of cleaning elements may be used in the broad practice of this invention. Alternatively, the bristles could be mounted to tuft blocks or sections by extending through suitable openings in the tuft blocks so that the base of the bristles is mounted within or below the tuft block.

The handle110extends along a longitudinal axis A-A and is connected to the head190. In the exemplary embodiment, the head190and the handle110are integrally formed as a single unitary structure using a molding, milling, machining or other suitable process. However, in other embodiments the handle110and the head190may 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. Whether the head190and the handle110are of a unitary or multi-piece construction (including connection techniques) is not limiting of the present invention, unless specifically claimed. In some embodiments of the invention, the head190may be detachable (and replaceable) from the handle110using techniques known in the art.

In the exemplified embodiment, the head190has a generally oval shape. However, the invention is not to be limited by the shape or contour of the head190unless so specified in the claims. Thus, the head190and the tooth cleaning elements191are generically illustrated herein, but those generic illustrations are not intended to limit the present invention.

Referring toFIGS. 1-4Bconcurrently, the oral care implement100will be further described. The handle110comprises a main body101that is integrally formed of a rigid material. The main body101comprises a first rigid longitudinal section120, a second rigid longitudinal section130and a hinge150. In the exemplified embodiment, the first rigid longitudinal section120is a rigid gripping section of the main body101and the second rigid longitudinal section130is a rigid neck section of the main body101. The hinge150is a portion of the handle110that is longitudinally positioned between the first rigid longitudinal section120(i.e., the rigid gripping section) and the second rigid longitudinal section130(i.e., the rigid neck section). The hinge150facilitates a pivoting or flexing motion of the handle110. Specifically, the hinge150forms a portion of the handle110about which the second rigid longitudinal section130pivots relative to the first rigid longitudinal section120upon application of a force F1to the head190. Thus, during brushing or any other activity that imparts the force F1to the head190in a direction normal to the longitudinal axis A-A, the second rigid longitudinal section130will flex and pivot about the hinge150in the direction of the force F1. This pivoting movement will be described in greater detail below with specific reference toFIGS. 13A-13C.

FIG. 4Aillustrates a side view of the oral care implement100in its biased position when there is no force acting on the head190. In the biased position, the second rigid longitudinal section130is substantially coaxial with the first rigid longitudinal section120.FIG. 4Billustrates a side view of the oral care implement100while the force F1is being applied to the head190. When the force F1is applied to the head190, the second rigid longitudinal section130pivots in the direction of the rear surface of the head193so as to achieve an acute angle relative to the first rigid longitudinal section120. InFIG. 4Bthe positioning of the second rigid longitudinal section130and the head190relative to the hinge150when the oral care implement100is in the biased position is illustrated in phantom lines to illustrate the range of flexibility. Of course, the oral care implement100can be designed so that the second rigid longitudinal section130is capable of more or less pivot/flexibility than that illustrated. The degree of pivot is dependent upon the thickness and density of a resilient material that forms a part of the hinge150as well as the thickness of a strut or struts that forms a part of the hinge150. The strut or struts and resilient material will be described in more detail below with regard toFIGS. 5-9.

The greater the force F1that is imparted to the head190, the greater the degree of flex/pivot of the second rigid longitudinal section130relative to the first rigid longitudinal section120. However, in certain embodiments a resilient material103(described below) included with the oral care implement100has a thickness that is sufficient to prevent over flexure of the second rigid longitudinal section130to prevent breakage of the handle110.

In the exemplified embodiment, the first rigid longitudinal section120is a gripping section of the handle110and the second rigid longitudinal section130is a neck section of the handle110. Thus, the first rigid longitudinal section120of the handle110is an elongated structure that provides the mechanism by which the user can hold and manipulate the oral care implement100during use. Specifically, during use of the oral care implement100the first rigid longitudinal section120rests within the palm of the user and the hinge150forms a bulbous gripping area for the thumb and forefinger of the user. Furthermore, the second rigid longitudinal section130forms the neck section of the handle110that is connected to the head190. It should be appreciated that the handle110can take on a wide variety of shapes, contours and configurations, none of which are limiting of the present invention unless specifically claimed. Thus, the handle110may comprise additional undulations and regions that are covered in a resilient material to enhance gripability and comfort.

The handle110comprises an outer surface102that is formed from the rigid material of each of the first and second rigid longitudinal sections120,130and from a resilient material103that is located in the region of the hinge150of the oral care implement100. The resilient material103provides a comfortable surface for the user to grip during use and enhances the flexibility of the second rigid longitudinal section130relative to the first rigid longitudinal section120as discussed above. The resilient material103forms a portion of the outer surface102of the handle110around the entire circumference of the handle110in the region of the hinge150.

The handle110extends along the longitudinal axis A-A from a proximal end121of the first rigid longitudinal section120to a distal end132of the second rigid longitudinal section130. Furthermore, the handle110has a length LHmeasured from the proximal end121of the first rigid longitudinal section120to the distal end132of the second rigid longitudinal section130. The hinge150is located at a distance DHfrom the distal end132of the second rigid longitudinal section130. The distance DHis preferably less than 50% of the length LHof the handle110, more preferably between 15% to 40% of the length LHof the handle110, and still more preferably between 20% to 35% of the length LHof the handle110. As described above, the location of the hinge150enables the hinge150to be located at or near a region of the handle110that a user would grip with his or her thumb and forefinger during use of the oral care implement100.

Referring toFIGS. 5-7concurrently, the oral care implement100is illustrated with the resilient material103removed to depict the components of the hinge150. In addition to the first and second rigid longitudinal sections120,130, the main body101of the handle110also comprises a longitudinal strut140. In the exemplified embodiment, the longitudinal strut140is a single longitudinal structure that extends substantially coaxially with the longitudinal axis A-A. However, the invention is not to be so limited and in certain other embodiments the longitudinal strut140can be formed by a plurality of transversely spaced apart struts, or a single strut centrally positioned within the handle110or positioned within the handle110near one side of the handle110.

In the exemplified embodiment, the longitudinal strut140is formed of rigid material. Thus, the entire main body101of the handle110(including the first rigid longitudinal section120, the second rigid longitudinal section130and the longitudinal strut140) is integrally formed of a rigid material, such as any rigid plastic material. Suitable plastics for the rigid material of the handle110include, without limitation, polymers and copolymers of ethylene, propylene, butadiene, vinyl compounds and polyesters such as polyethylene terephthalate.

In certain embodiments, the first rigid longitudinal section120, the second rigid longitudinal section130and the longitudinal strut140are integrally formed of the same rigid material. However, the invention is not to be so limited in all embodiments and the longitudinal strut140can be formed of a different rigid material than the first and second rigid longitudinal sections120,130in other embodiments. Moreover, as will be described in more detail below, despite the longitudinal strut140being formed of the same material as the first and second rigid longitudinal sections120,130, the longitudinal strut140is more flexible than the first and second rigid longitudinal sections120,130because the longitudinal strut140is a portion of the main body101of the handle110that has a reduced thickness.

It should be appreciated that the term rigid, as used herein with regard to the first and second longitudinal sections120,130, is not to be limited to a completely stiff and inflexible structure. Rather, the term rigid is used herein to describe the structure of the first and second longitudinal sections120,130relative to the hinge150. Thus, in certain embodiments the first and second longitudinal sections120,130may be capable of a certain degree of flexure, but are more firm than the hinge150so that during brushing the handle110pivots about the hinge150. Moreover, it should be appreciated that the rigid sections, such as the first and second longitudinal sections120,130of the handle110, can comprise additional hinge areas or areas of increased flexibility other than or in addition to the hinge150in certain embodiments.

The first rigid longitudinal section120extends along the longitudinal axis A-A from the proximal end121to a distal end122and the second rigid longitudinal section130extends along the longitudinal axis A-A from a proximal end131to the distal end132. The longitudinal strut140extends between and connects the distal end122of the first rigid longitudinal section120to the proximal end131of the second rigid longitudinal section130. As discussed above, the head190is connected to the handle110, and specifically to the distal end132of the second rigid longitudinal section130of the handle110.

The first rigid longitudinal section120comprises a first transverse shoulder123at its distal end122. Moreover, the first transverse shoulder123comprises a bulbous body124. In the exemplified embodiment, the first rigid longitudinal section120terminates in the bulbous body124. Furthermore, in exemplified embodiment the bulbous body124is a semi-spheroid. However, the invention is not to be so limited in all embodiments and the bulbous body124can take on other shapes. The second rigid longitudinal section130comprises a second transverse shoulder133at its proximal end131. Moreover, the second transverse shoulder133comprises a basin134having a floor135. In the exemplified embodiment, the second rigid longitudinal section130terminates in the basin134. The distal end122of the first rigid longitudinal section120is adjacent the proximal end131of the second rigid longitudinal section130. However, as described below, the first and second transverse shoulders123,133, and hence also the bulbous body124and the basin134, are spaced from one another.

Although the invention is illustrated and described herein such that the first rigid longitudinal section120(i.e., the gripping section) terminates in the bulbous body124and the second rigid longitudinal section130(i.e., the neck section) terminates in the basin134, the invention is not to be so limited. Thus, in certain embodiments the first rigid longitudinal section120may comprise and terminate in a basin while the second rigid longitudinal section130may comprise and terminate in a bulbous body. Thus, according to the present invention, one of the first rigid longitudinal section120(i.e., the gripping section) or the second rigid longitudinal section130(i.e., the neck section) comprises a bulbous body and the other one of the first rigid longitudinal section120or the second rigid longitudinal section130comprises a basin.

The longitudinal strut140extends axially from a first end141to a second end142and transversely from a front surface144to a rear surface145. Thus, the first end141of the longitudinal strut140is connected to the bulbous body124, and more specifically to the first transverse shoulder123, and the second end142of the longitudinal strut140is connected to the floor135of the basin134, and more specifically to the second transverse shoulder133. In certain embodiments, the longitudinal strut140extends axially from an apex of the bulbous body124. Moreover, in certain embodiments the apex of the bulbous body124is a convex surface. Due to its axial connection between the floor135of the basin134and the bulbous body124, the longitudinal strut140provides separation between the bulbous body124and the basin134such that the bulbous body124and the floor135of the basin134are separated by a separation gap126. The separation gap126is an annular channel that circumferentially surrounds the longitudinal strut140. The separation gap126is filled with the resilient material103in a manner such that resilient material103encases the longitudinal strut140(FIGS. 12 and 12A).

The separation gap126generally comprises a flexure limiting gap109and a flexure facilitating gap119. The flexure limiting gap109is located adjacent the rear surface145of the longitudinal strut140and the flexure facilitating gap119is located adjacent a front surface144of the longitudinal strut. More specifically, the flexure facilitating gap119separates the first and second transverse shoulders123,133from one another. Each of the flexure limiting gap109and the flexure facilitating gap119are filled with the resilient material103. The flexure limiting gap109and the flexure facilitating gap119work together to facilitate pivoting of the second rigid longitudinal section130relative to the first rigid longitudinal section120while preventing over flexure, permanent deformation and/or breakage of the oral care implement100.

The hinge150generally comprises the longitudinal strut140and the resilient material103which encases the longitudinal strut140. More specifically, the hinge150comprises the bulbous body124, the basin134, the longitudinal strut140and the resilient material103that is in the separation gap126. Thus, the hinge150, and more specifically the longitudinal strut140and the resilient material103encasing the longitudinal strut140, enables the second rigid longitudinal section130to pivot relative to the first rigid longitudinal section120upon the force F1being applied to the head190as described above with reference toFIGS. 4A and 4B. It should be appreciated that because the hinge150comprises the longitudinal strut140, the longitudinal strut140is located at the distance DHfrom the distal end132of the second rigid longitudinal section130.

In the exemplified embodiment, the outer surface102of the handle110of the oral care implement100comprises an axial groove104that extends axially from the hinge150toward the proximal end121of the first rigid longitudinal section120(i.e., the gripping section). The axial groove104is filled in with the resilient material103(FIGS. 12 and 12A). Thus, the resilient material103that fills in the axial groove104forms a gripping surface for the user, and specifically for the user's thumb. Forming portions of the outer surface102of the handle110out of the resilient material103prevents mishandling of the oral care implement100during use under wet conditions because the resilient material103enhances gripability of the handle110.

In the exemplified embodiment, the bulbous body124comprises a transverse channel105extending therethrough. As will be discussed below with reference toFIGS. 13A-13C, the transverse channel105acts as a secondary flexure limiting gap that provides additional flex/pivot about the hinge150. The transverse channel105is formed into a rear surface108of the bulbous body124and forms a transverse passageway through the bulbous body124. However, the transverse channel105can be omitted in other embodiments (FIGS. 13, 14A and 14B, discussed below).

In the exemplified embodiment, the oral care implement100comprises a first flexure limiting block107protruding from the rear surface108of the bulbous body124and a second flexure limiting block106protruding from the floor135of the basin134. Each of the first and second flexure limiting blocks107,106are comprised by and formed integrally with the main body101of the oral care implement100. More specifically, the first flexure limiting block107extends axially from the bulbous body124into the separation gap126and the second flexure limiting block106extends axially from the floor135of the basin134into the separation gap126. In certain embodiments, the first transverse shoulder123comprises a convex surface, and the first flexure limiting block107is connected to and protruding from the convex surface of the first transverse shoulder123. The second flexure limiting block106is connected to the second transverse shoulder133and to the rear surface145of the strut140.

The first and second flexure limiting blocks107,106are circumferentially aligned with one another and with the rear surface193of the head190. Furthermore, despite each of the first and second flexure limiting blocks107,106extending into the separation gap126, the first and second flexure limiting blocks107,106are axially spaced apart from one another. Thus, the flexure limiting gap109is formed between the first and second flexure limiting blocks107,106. As illustrated inFIG. 12A, the resilient material103is disposed within and fills in the flexure limiting gap109. Furthermore, the resilient material103encases each of the longitudinal strut140, the first flexure limiting block107and the second flexure limiting block106.

In the exemplified embodiment, each of the first and second flexure limiting blocks107,106comprise a substantially rectangular shape. Of course, the invention is not to be so limited in all embodiments and in certain other embodiments the first and second flexure limiting blocks107,106can take on other shapes. Furthermore, in certain embodiments the first and second flexure limiting blocks107,106have the same shape and in certain other embodiments the first and second flexure limiting blocks107,106can have different shapes.

Due to the first and second flexure limiting blocks107,106, the flexure limiting gap109and the resilient material103therein, the second rigid longitudinal section130is able to pivot relative to the first rigid longitudinal section120about the hinge150. Specifically, when the force F1is applied to the head190of the oral care implement100, the resilient material103in the flexure limiting gap109becomes compressed and the first and second flexure limiting blocks107,106come into contact with one another. Thus, the first and second flexure limiting blocks107,106prevent overflexing the handle110to the breaking point of the handle110. However, one or both of the flexure limiting blocks106,107may be omitted in certain other embodiments as will be discussed below with reference toFIG. 13.

Referring toFIGS. 8-10Bconcurrently, the oral care implement100will be further described. In the exemplified embodiment as has been described herein above, the basin134forms the proximal end131of the second rigid longitudinal section130(i.e., the rigid neck section). Furthermore, the second rigid longitudinal section130comprises a first flange136and a second flange137. The first and second flanges136,137extend axially from the floor135of the basin134to form opposing sidewalls of the basin134. Furthermore, the first and second flanges136,137also flare radially outward from the longitudinal axis A-A. Thus, the first flange136forms a first sidewall146of the basin134and the second flange137forms a second sidewall147of the basin134. The first flange136is circumferentially spaced apart from the second flange137by a first valley138that is circumferentially aligned with the rear surface193of the head190and a second valley139that is circumferentially aligned with the front surface192of the head190. Thus, as a result of the flanges136,137and valleys138,139, the second rigid longitudinal section130terminates in an undulating annular edge.

FIGS. 10A and 10Bare illustrated with the plane angle measurements 0°, 90° 180° and 270° to exemplify the positioning of the flanges136,137and valleys146,147relative to the front and rear surfaces192,193of the head190. Thus,FIGS. 10A and 10Billustrate that the first and second valleys146,147are circumferentially aligned with the front and rear surfaces192,193of the head190, respectively, as discussed above.

Referring toFIGS. 9 and 11, a schematic representation of a transverse cross-section taken through the longitudinal strut140at an axial location171is illustrated. In the exemplified embodiment, the longitudinal strut140has a thickness TSmeasured from the front surface144of the longitudinal strut140to the rear surface145of the longitudinal strut140. Furthermore, the longitudinal strut140has a width WSmeasured from a first side surface154of the longitudinal strut140to a second side surface155of the longitudinal strut140. The width WSof the longitudinal strut140is greater than the thickness TSof the longitudinal strut140.

In the exemplified embodiment, the longitudinal strut140comprises a substantially rectangular transverse cross-sectional area. Of course, the invention is not to be so limited in all embodiments and in certain other embodiments the longitudinal strut140can have other cross-sectional shapes. Furthermore, as noted above, in still other embodiments the longitudinal strut140may be formed by a plurality of struts that are transversely spaced from one another.

The handle110comprises a first transverse cross-sectional area taken at the axial location171of the longitudinal strut140and the longitudinal strut140has a second transverse cross-sectional area taken at the axial location171. The second transverse cross-sectional area of the longitudinal strut140at the axial location171is in a range between 7% to 35% of the first transverse cross-sectional area of the handle110at the axial location171.

Referring to12and12A, as discussed above, the separation gap126between the bulbous body124and the floor135of the basin134is filled with the resilient material103. In certain embodiments, the separation gap126is filled with the resilient material103in a manner such that resilient material103encases the longitudinal strut140. Furthermore, the resilient material103also encases the floor135of the basin134and the bulbous body124such that in the fully assembled oral care implement100illustrated inFIGS. 1-3, neither the basin134nor the bulbous body124is exposed because it is entirely covered by the resilient material103(seeFIGS. 1-3). In certain embodiments, the resilient material103is an injection molded thermoplastic elastomer. However, the invention is not to be so limited in all embodiments and other materials that can provide resiliency and flexibility to the handle110as has been described herein can be used.

In the exemplified embodiment illustrated inFIGS. 12 and 12A, the rear surface193of the head190is facing a counter-clockwise direction DCCsuch that the force F1acting on the head190of the oral care implement100will result in the second rigid longitudinal section130pivoting relative to the first rigid longitudinal section120in the counter-clockwise direction DCC. As will be discussed below with reference toFIGS. 13A-13C, the first and second flexure limiting blocks107,106limit the pivoting of the second rigid longitudinal section130relative to the first rigid longitudinal section120in the counter-clockwise direction DCC.

Referring toFIGS. 13A-13C, the pivoting of the second rigid longitudinal section130relative to the first rigid longitudinal section120will be further described. As discussed in detail above, the oral care implement100of the present invention includes a longitudinal strut140that extends between and connects the first rigid longitudinal section120to the second rigid longitudinal section130. Furthermore, in addition to the longitudinal strut140, the main body101further comprises an oblique strut160that is formed into the first transverse shoulder123and forms a part of the hinge150. The transverse channel105forms the oblique strut160into the first transverse shoulder123. In certain embodiments, the longitudinal strut140can be considered a first strut whereas the oblique strut160can be considered a second strut.

In the exemplified embodiment, the longitudinal strut140extends along a first axis B-B and the oblique strut160extends along a second axis C-C. The first axis B-B and the second axis C-C intersect at an oblique angle. In the exemplified embodiment, the longitudinal strut140extends in a substantially axial direction relative to the longitudinal axis A-A of the handle110and the oblique strut160extends in a substantially oblique direction relative to the longitudinal strut140. However, the invention is not to be so limited in all embodiments and in certain other embodiments the oblique strut160can be oriented in a similar, longitudinal direction relative to the longitudinal strut140.

The flexure facilitating gap119is the space between the first transverse shoulder123of the first rigid longitudinal section120of the main body101of the handle110and the second transverse shoulder133of the second rigid longitudinal section130of the main body101of the handle110. The flexure facilitating gap119has a first width W1extending between the first transverse shoulder123of the first rigid longitudinal section120and the second transverse shoulder133of the second rigid longitudinal section130. Furthermore, the flexure limiting gap109is the space between the first flexure limiting block107and the second flexure limiting block106. The flexure limiting gap109has a second width W2extending between the first flexure limiting block107and the second flexure limiting block106. The second width W2is less than the first width W1. In certain embodiments, a ratio of the second width W2to the first width W1is in a range of 0.1 to 0.6.

InFIG. 13A, the oral care implement100is illustrated in the biased state as has been described above wherein there is no force acting on the second rigid longitudinal section130of the main body101relative to the first rigid longitudinal section120of the main body101. In this biased state, a first reference line X1is aligned with a bottom surface of the second flexure limiting block106. The first reference line X1will be described in more detail below to discuss the degree of pivot that occurs when a force is applied to the head190of the oral care implement.

Referring now toFIGS. 13A and 13Bconcurrently, the oral care implement100will be described with regard to the pivot of the second rigid longitudinal section130relative to the first rigid longitudinal section120when an initial force F1is applied to the head. InFIG. 13B, the oral care implement100is illustrated with the force F1being applied to the head (the head is not illustrated in this figure in order to provide a close-up of the pivoting movement taking place at the hinge150). During initial application of the force F1, the second rigid longitudinal section130of the main body101initially pivots relative to the first rigid longitudinal section120of the main body101about the longitudinal strut140a first angle θ1. The degree of the first angle θ1can be determined by comparing the first reference line X1with a second reference line X2that is aligned with the bottom surface of the second flexure limiting block106after the initial pivot. In certain embodiments, the first angle θ1is less than or equal to about 25°, and in certain other embodiments the first angle θ1is between 10°-20°. The first angle θ1is such as to prevent permanent deformation or breakage of the longitudinal strut140. During initial application of the force F1, there is no pivoting that occurs about the oblique strut160and thus a third reference line Z1is aligned with the bottom surface of the first flexure limiting block107.

During initial application of the force F1, the resilient material103in the flexure limiting gap109compresses and the second flexure limiting block106pivots about the longitudinal strut140into the flexure limiting gap109towards the first flexure limiting block107. The first and second flexure limiting blocks107,106prevent over flexure of the oral care implement100. More specifically, mechanical interference between the first and second flexure limiting blocks107,106limits pivoting of the second rigid longitudinal section130relative to the first rigid longitudinal section120in the counter-clockwise direction DCCwhen the rear surface193of the head190is facing the counter-clockwise direction DCCas discussed above with reference toFIG. 12. In the exemplified embodiment, the first and second flexure limiting blocks107,106remain spaced from one another by the resilient material103in the flexure limiting gap109even after the pivoting motion illustrated inFIG. 13B. Of course, the invention is not to be so limited and in certain other embodiments the mechanical interference may be achieved via actual contact between the first and second flexure limiting blocks107,106.

Referring toFIGS. 13B and 13Cconcurrently, the oral care implement100will be described after a subsequent pivoting motion of the second rigid longitudinal section130relative to the first rigid longitudinal section120. The mechanical interference between the first and second flexure limiting blocks107,106discussed above causes pivoting of the second rigid longitudinal section130relative to the first rigid longitudinal section120to transition from the longitudinal strut140to the oblique strut160. Thus, upon further application of the force F1after the mechanical interference occurs, the second rigid longitudinal section160begins to pivot about the oblique strut160rather than about the longitudinal strut140. Thus, the subsequent pivot causes the resilient material103positioned within the transverse channel105to compress such that the bottom surface of the first flexure limiting block107pivots downwardly into the transverse channel105and the second rigid longitudinal section130pivots relative to the first rigid longitudinal section120about the oblique strut160a second angle θ2.

The degree of the second angle θ2can be determined by comparing the third reference line Z1with a fourth reference line Z2that is aligned with the bottom surface of the first flexure limiting block107after the subsequent pivot. In certain embodiments, the second angle θ2is less than the first angle θ1and in certain other embodiments the second angle θ2is greater than the first angle θ1. The second angle θ2assists in preventing permanent deformation or breakage of the oblique strut160. During pivoting about the oblique strut160, the first angle θ1remains as discussed above, such as less than 25°.

The longitudinal strut140and the oblique strut160connect the first rigid longitudinal section120and the second rigid longitudinal section130such that a first torque is required to pivot the second rigid longitudinal section130relative to the first rigid longitudinal section120about the longitudinal strut140the first angle θ1and a second torque is required to subsequently pivot the second longitudinal section130relative to the first rigid longitudinal section120about the oblique strut160a second angle θ2, the second torque being greater than the first torque. Thus, a greater amount of force or torque is used during pivoting about the oblique strut160than is used during pivoting about the longitudinal strut140.

Referring toFIGS. 11 and 14concurrently, the relative transverse cross-sectional areas of the longitudinal strut140and the oblique strut160will be described.FIG. 11illustrates a cross-section taken at a point along the first axis B-B andFIG. 14illustrates a cross-section taken at a point along the second axis C-C. As discussed above, the longitudinal strut140has a width Ws and a thickness TS. The longitudinal strut140also has a first transverse cross-sectional area that is equal to the width WStimes the thickness TS. The oblique strut160has a width WOSand a thickness TOS. The oblique strut160also comprises a second transverse cross-sectional area that is equal to the width WOStimes the thickness TOS. The second transverse cross-sectional area of the oblique strut160is greater than the first transverse cross-sectional area of the longitudinal strut140. This difference in the cross-sectional areas of the longitudinal strut140and the oblique strut160facilitates that a larger torque is required to pivot the second rigid longitudinal section130relative to the first rigid longitudinal section120about the oblique strut160than is required to pivot the second rigid longitudinal section130relative to the first rigid longitudinal section120about the longitudinal strut140.

Referring toFIGS. 15 and 15A, an oral care implement200in accordance with a second embodiment of the present invention will be described. The oral care implement200is similar to the oral care implement100in many aspects, and therefore similar features will be similarly numbered except that the 200-series of numbers will be used. Furthermore, the specific structure of features of the oral care implement200that are similar to or the same as features of the oral care implement100will not be repeated in the interest of brevity.

The oral care implement200comprises a handle210that is connected to a head290. The head290comprises a front surface292and an opposing rear surface293with tooth cleaning elements291extending outwardly from the front surface292. Specifically, the handle210comprises a main body201comprising a first rigid longitudinal section220, a second rigid longitudinal section230and a hinge250. The first rigid longitudinal section220is spaced from the second rigid longitudinal section230by a gap226. A flexible strut240extends longitudinally from the first rigid longitudinal section220and connects to the second longitudinal section230. Thus, the first rigid longitudinal section220, the second rigid longitudinal section230and the flexible strut240are integrally formed of a rigid plastic material, such as, without limitation, polymers and copolymers of ethylene, propylene, butadiene, vinyl compounds and polyesters such as polyethylene terephthalate.

The first rigid longitudinal section220terminates at its proximal end222in a bulbous body224having a convex outer surface218. Thus, in this embodiment the flexible strut240extends axially from the convex outer surface218of the bulbous body224of the first rigid longitudinal section. The flexible strut240comprises a first end241that is connected to the convex outer surface218of the bulbous body224at the proximal end222of the first rigid longitudinal section220and a second end242that is connected to a distal end231of the second rigid longitudinal section230.

The gap226is filled with a resilient material203, such as a thermoplastic elastomer. Of course, the resilient material203is not limited to being a thermoplastic elastomer and other resilient materials may be used as desired. The resilient material203encases and circumferentially surrounds the flexible strut240. The resilient material203also encases the bulbous body224and the distal end231of the second rigid longitudinal section230, which in certain embodiments comprises a basin (such as described above with regard to the oral care implement100).

The combination of the flexible strut240and the resilient material203combine to form the hinge250of the oral care implement200. The hinge250forms a region of the handle110upon which the second rigid longitudinal section230pivots relative to the first rigid longitudinal section220upon a brushing force, such as the force F1described above with regard to the oral care implement100, being applied to the head290. The main difference between the oral care implement200and the oral care implement100is that the oral care implement200omits the flexure limiting blocks106,107and the transverse channel105. Furthermore, the surface of the bulbous body224of the oral care implement200from which the flexible strut240extends is convex whereas the surface of the bulbous body124of the oral care implement100from which the longitudinal strut140extends is relatively flat. Nonetheless, operation and flexibility of the oral care implement200is similar to that of the oral care implement100described above.

Turning toFIGS. 16A and 16B, an oral care implement300in accordance with a third embodiment of the present invention will be described. The oral care implement300is similar to the oral care implement100in many aspects, and therefore similar features will be similarly numbered except that the 300-series of numbers will be used. Furthermore, the specific structure of features of the oral care implement300that are similar to or the same as features of the oral care implement100will not be repeated in the interest of brevity. InFIGS. 16A and 16B, only a close-up view of the hinge section350of the oral care implement300is illustrated. It should be understood that all components and structures of the oral care implement300that are not illustrated are the same as or similar to components from either of the oral care implements100,200previously described herein.

The oral care implement300comprises a first rigid longitudinal section320, a second rigid longitudinal section330and a hinge section350. The hinge350is formed by a bulbous body324formed at a proximal end322of the first rigid longitudinal section320, a basin334formed at a proximal end331of the second rigid longitudinal section330and a flexible strut340that extends between the first and second rigid longitudinal sections320,330. The first rigid longitudinal section320is spaced from the second rigid longitudinal section330by a gap326. Although not illustrated, the oral care implement300comprises a resilient material that fills in the gap326to provide a flexible connection between the first rigid longitudinal section320and the second rigid longitudinal section330about the hinge350as has been described herein above with regard to the oral care implements100,200.

The oral care implement300also comprises a flexure limiting block306to prevent overflexing of the second rigid longitudinal section330relative to the first rigid longitudinal section320about the hinge350. However, the oral care implement300omits a second flexure limiting block and a transverse channel extending through the bulbous body, both of which were described herein above with regard to the oral care implement100. Thus, the oral care implement300is similar to the oral care implement100with the exception that the oral care implement300omits the second flexure limiting block and the transverse channel. As a result of the omission of the aforementioned components, the oral care implement300is also devoid of an oblique (or second) strut that facilitates a subsequent pivoting motion as has been described herein above.

While the foregoing description and drawings represent the exemplary embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope of the present invention as defined in the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other specific forms, structures, arrangements, proportions, sizes, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will appreciate that the invention may be used with many modifications of structure, arrangement, proportions, sizes, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims, and not limited to the foregoing description or embodiments.