Toothbrushes

Information

  • Patent Grant
  • 6699038
  • Patent Number
    6,699,038
  • Date Filed
    Wednesday, September 19, 2001
    22 years ago
  • Date Issued
    Tuesday, March 2, 2004
    20 years ago
Abstract
A toothbrush which includes a handle with a head portion at one end, a recess in the head, a bristle pack located in the recess with the bristles attached by one end to the base of the recess, the recess opening being bounded by inwardly directed shoulders, and the outer extremities of the bristles lying in abutting relationship with the inner faces of the shoulders. There is a fluid supply line provided along or through the handle and communicating with the recess. Preferably, the bristle pack is formed by a number of clusters of bristles, it being the outermost clusters that are in close abutting relationship with the edges of the shoulders of the recess, and adjacent clusters at least at the edges of the pack being in close but spaced relationship.
Description




BACKGROUND




This invention relates to toothbrushes and in particular toothbrushes for use in oral hygiene systems suited for use by bedridden users.




Conventionally, water is applied to the bristled head of a toothbrush to assist the cleaning action of a dentifrice applied to its bristles, and following brushing, it is usual to rinse the mouth. To the able bodied or to those able to sit upright without undue difficulty, cleaning the teeth is not particularly troublesome.




However, when it is the case of a bedridden patient, not able to sit upright, or only able to sit upright with considerable difficulty and discomfort, cleaning the teeth is particularly troublesome, and especially rinsing the mouth, as neither the application of fluid to assist the action of the dentifrice nor subsequent rinsing of the mouth can be effected in conventional manner with the patient in the prone position.




It is known from such as U.S. Pat. No. 4,672,953 to provide a toothbrush with first and second passageway means through the handle for the supply of fluid to the bristles of the brush and its removal from the patient's mouth by suction, in an attempt to overcome the difficulties mentioned above in relation to patients who must, of necessity, remain in a prone position.




However, such a construction still leaves room for improvement in the sense that with prone patients it can frequently occur that the patient's mouth inadvertently closes on to the toothbrush during use causing an undesired build-up of vacuum during removal of spent fluid. This problem is attended to in European Patent Number 0557337B where a toothbrush construction is provided that ensures that in the circumstance when a patient's mouth does inadvertently close on to the toothbrush there is the substantial guarantee that a vacuum buildup in the mouth is prevented.




OBJECT AND SUMMARY




The object of the present invention is to provide a toothbrush construction of simpler and less expensive construction but with the same time a significantly improved ability to provide and remove fluid and prevent a vacuum build-up.




According to the present invention, a toothbrush comprises a handle with a head portion at one end, a recess in the head, a bristle pack located in the recess with the bristles attached by one end to the base of the recess, the recess opening being bounded by inwardly directed shoulders, and the outer extremities of the bristles lying in abutting relationship with the inner faces of the shoulders, and there being a fluid supply line provided along or through the handle and communicating with the recess. Preferably, the bristle pack is formed by a number of clusters of bristles, it being the outermost clusters that are in close abutting relationship with the edges of the shoulders of the recess, and adjacent clusters at least at the edges of the pack being in close but spaced relationship.




Thus, and in use, water or cleansing agent cam be supplied to the bristle pack to emerge from the bristle pack during teeth cleaning, and simultaneously, the connection of the vacuum line to a source of reduced pressure or a vacuum pump causes the extraction of water or cleansing fluid from the mouth.




Most desirably, the bristle pack is dimensioned such that it locates in the recess in the bristle head with clearance on all four sides, the outer bristles or bristle clusters extending vertically from the base of the recess in alignment with the edges of the flanges at the edges of the recess to ensure that vacuum is provided around the whole of the bristle pack.




By having the bristles or bristle clusters at the edge of the bristle pack in abutting engagement with the faces of the shoulders at the edges of the recess, there is a major concentration of vacuum created around the base of the bristles between adjacent bristles or bristle clusters not only at the edges of the bristle pack, but also over the whole of its area, maximizing the extraction of fluid from the mouth of the user.




Able bodied users can deal adequately with fluid in the mouth should it be that removal of fluid is not at the same rate as the supply of water or cleansing fluid. However, with users who must remain prone, are ill or semi-conscious, it is essential that control of water or cleansing fluid supply to the mouth is balanced with the rate of extraction, to ensure that the mouth of the user does not fill with fluid.




Equally, it is important that if such users close their mouth around the toothbrush, an excess vacuum does not build up in the mouth. It is therefore desirable that there is an air vent means located on the handle and extending along the handle form a position in close proximity to the bristles, the air vent means having an inlet to longitudinal spaced relationship along the length of the handle to prevent the inlet being closed by the lips of the user.




The vent may be a tube-like member located on the handle, but preferably the vent is formed by at least one and preferably two diametrically opposed passageways within the confines of the handle, with longitudinally spaced access holes through the outer wall of the passageway.




To enable the toothbrush of the invention to be used in conjunction with a machine such as is disclosed in European Patent Number 0557337B, the end of the handle remote form the bristle head may be fashioned as a plug-like connector, the machine being provided with a mating plug-like connector such that the first chamber can be connected to a source of vacuum, i.e., to a fluid pump on the machine, by one simple act. It enables a brush to be dedicated to a particular use in the circumstances where it is the machine of European Patent Number 0557337B, and in use as in such as a hospital.











BRIEF DESCRIPTION OF THE DRAWINGS




The organization and manner of the structure and operation of the invention, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings, wherein like reference numerals identify like elements in which:





FIG. 1

is a side elevational view of a toothbrush which is in accordance with an embodiment of the present invention;





FIG. 2

is a top plan view of the toothbrush shown in

FIG. 1

;





FIG. 3

is an end view of the toothbrush shown in

FIGS. 1 and 2

;





FIG. 4

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


4





4


of

FIG. 2

;





FIG. 5

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


5





5


of

FIG. 2

;





FIG. 6

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


6





6


of

FIG. 2

;





FIG. 7

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


7





7


of

FIG. 2

;





FIG. 8

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


8





8


of

FIG. 2

;





FIG. 9

is a cross-sectional view of the toothbrush shown in

FIGS. 1 and 2

, taken along line


9





9


of

FIG. 2

;





FIG. 10

is a top plan view of a bottom portion of the toothbrush shown in

FIG. 1

;





FIG. 11

is a side elevational view of a toothbrush which is similar to that which is shown in

FIG. 1

, but where the toothbrush has a bend;





FIG. 12

is a side elevational view of a toothbrush which is in accordance with another embodiment of the present invention;





FIG. 13

is a top plan view of the toothbrush shown in

FIG. 12

;





FIG. 14

is an enlarged top plan view of an end of the toothbrush shown in

FIGS. 12 and 13

;





FIG. 15

is an enlarged side elevational view of the end of the toothbrush shown in

FIGS. 12 and 13

;





FIG. 16

is a perspective view of a toothbrush which is in accordance with yet another embodiment of the present invention;





FIG. 17

is a cross sectional view of a toothbrush which is in accordance with still yet another embodiment of the present invention;





FIG. 18

is a cross-sectional view of the head of a toothbrush which in accordance with still yet another embodiment of the present invention, wherein bristles are attached directly to a base; and





FIG. 19

is a perspective view of an end of a toothbrush which is in accordance with still yet another embodiment of the present invention, wherein there are a plurality of ribs on the surface of the toothbrush to prevent a build up of vacuum.











DESCRIPTION




While the invention may be susceptible to embodiment in different forms, there are shown in the drawings, and herein will be described in detail, specific embodiments with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention, and is not intended to limit the invention to that as illustrated and described herein.




Shown in the drawings are several toothbrushes which are in accordance with various embodiments of the present invention. Specifically,

FIGS. 1 and 2

show a toothbrush


10




a


which is in accordance with a first embodiment of the present invention,

FIG. 11

shows a toothbrush


10




b


which is in accordance with a second embodiment of the present invention,

FIGS. 12 and 13

show a toothbrush


10




c


which is in accordance with a third embodiment of the present invention,

FIG. 16

shows a toothbrush


10




d


which is in accordance with a fourth embodiment of the present invention,

FIG. 17

shows the cross-sectional profile of a toothbrush


10




e


which is in accordance with a fifth embodiment of the present invention,

FIG. 18

is a cross-sectional view of the head of a toothbrush


10




f


which in accordance with a sixth embodiment of the present invention, and

FIG. 19

is a perspective view of an end of a toothbrush


10




g


which is in accordance with a seventh embodiment of the present invention. Each of the toothbrushes


10




a


-


10




g


provide fluid supply, suction for removing the fluid from a user's mouth, and vent means for preventing an excess vacuum from building up in the mouth. Additionally, each of the toothbrushes


10




a


-


10




g


have a relatively simple and inexpensive construction.




The toothbrush


10




a


shown in

FIGS. 1 and 2

will first be described in detail, and then the other toothbrushes


10




b


-


10




g


will be described with emphasis on the differences. With regard to the toothbrush


10




a


shown in

FIGS. 1 and 2

,

FIG. 3

shows an end view thereof, and

FIGS. 4-9

show various cross-sectional views taken along corresponding lines of

FIG. 2

(i.e.

FIG. 4

is a cross-sectional view along line


4





4


of

FIG. 2

,

FIG. 5

is a cross-sectional view along line


5





5


of

FIG. 2

, etc.).




The toothbrush


10




a


shown in

FIGS. 1 and 2

has a first chamber in the form of a hollow handle


20


to provide a passageway


22


(see

FIGS. 5-10

) for vacuum, there being a connection


24


to the passageway


22


, which allows connection of the passageway


22


to a source of vacuum. Extending through the handle


20


is a fluid supply line


26


, there being a connection


28


to the fluid supply line


26


, which allows connection of the fluid supply line


26


to an appropriate source of fluid to be delivered to the mouth of a patient.




At the closed end of the handle is a bristle head


30


in which are located packed bristles


32


, the supply line


26


for fluid emerging directly in the center of the packed bristles


32


. The bristles


32


are surrounded by an area or opening


34


that can be a series of slots or can be a surface through which are provided a series of holes whereby to communicate the area immediately around the bristles


32


with the interior of the bristle head


30


and hence to the vacuum passageway


22


.




As shown in

FIG. 2

, on the surface of the handle


20


, to the side from which the bristles


32


emerge, is a longitudinal groove


40


. As will be described later herein, the longitudinal groove


40


functions as a vent to prevent build up of vacuum in the mouth of a user if the user closes her or her mouth onto the toothbrush


10




a.






As shown in

FIGS. 4-9

, the toothbrush


10




a


includes a lower portion


42


and an upper portion


44


which is attached, such as via welding, an adhesive, etc.) to the lower portion


42


. As shown in

FIGS. 4-9

, the lower portion


42


and upper portion


44


mate to form the passageways


22


and


24


for vacuum and fluid, respectively.

FIG. 10

shows the lower portion


42


removed from the upper portion


44


. As shown in

FIG. 10

, the lower portion


42


provides the connections


24


and


28


to vacuum and fluid, respectively. As shown in

FIGS. 4 and 5

, the upper portion


44


includes a pad


50


through which the fluid line


26


emerges. The bristles


32


are attached directly to the top surface of the pad


50


. Alternatively, as shown in

FIG. 18

, the bristles


32


may be attached directly to a surface of the lower portion


42


.




As shown in

FIGS. 4 and 5

, a rim


52


is fitted to the pad


50


. Specifically, a ridge


54


of the rim


52


is fitted under a lip


56


on the pad


50


. The rim


52


includes upper interned edges or shoulders


60


which contact the outermost bristles. The rim


52


creates a recess


62


from which the bristles


32


emerge. The contact between the outermost bristles and the upper interned edges


60


of the rim


52


provides for enhanced concentration of vacuum withdrawal of spent fluid and debris through the bristles


32


. Additionally, the openings


34


into the vacuum passageway


22


(see

FIG. 5

) is within the area (i.e. recess


62


) defined by the rim


52


.




As shown in

FIGS. 2

,


8


and


9


, the toothbrush


10




a


, and specifically the upper portion


44


thereof, provides structure for receiving a placard


70


for identifying, for example, a patient. The structure may include inwardly extending flanges


72


which define a channel


74


for receiving the placard


70


(the placard


70


is not shown in

FIGS. 8 and 9

, but is shown in FIG.


2


).




In use, and with connection


24


attached to a source of vacuum and connection


26


attached to a source of fluid, the toothbrush


10




a


can be placed within the mouth of a patient to brush the patients, teeth, the simultaneous application of an appropriate fluid and its removal is to the considerable advantage of particularly a prone or comatose patient in allowing a proper cleansing of the teeth without the patient chocking or there being spillage of fluid from the patient's mouth. In a circumstance where the patient's mouth inadvertently closes onto the toothbrush


10




a


, the length of groove


40


is such that the patient's mouth cannot close beyond its end, and consequently at least a portion of the groove


40


remains exposed to allow air to be drawn into the patient's mouth and hence prevent vacuum applied through the bristle head


30


to cause an unwanted build up of vacuum in the mouth of the patient.




The toothbrush


10




b


shown in

FIG. 11

is very much like the toothbrush


10




a


shown in

FIGS. 1 and 2

(and FIGS.


3


-


10


), and includes bristles


32


, rim


52


and a handle


20




b


. The toothbrush


10




b


differs from toothbrush


10




a


in that toothbrush


10




b


includes a bend, i.e. handle


20




b


is angled. This provides that the toothbrush


10




b


can be placed on a surface with the head held clear of the surface.




The toothbrush


10




c


shown in

FIGS. 12 and 13

(see also

FIGS. 14 and 15

) is very much like the toothbrush


10




a


shown in

FIGS. 1 and 2

(and FIGS.


3


-


10


), except the toothbrush


10




c


does not include any rim


52


. The toothbrush


10




c


includes a groove


40


and an opening


34


into the vacuum passageway


22


, as well as bristles


32


and a fluid supply inlet


26


. However, unlike with toothbrush


10




a


, the opening


34


, bristles


32


and fluid supply inlet


26


of toothbrush


10




c


are not contained with a rim (such as rim


52


of toothbrush


10




a


).




The toothbrush


10




d


shown in

FIG. 16

is very much like toothbrush


10




a


, and is very much like toothbrush


10




b


in that toothbrush


10




d


includes a bend. However, toothbrush


10




d


is different in that, in place of the longitudinal groove


40


, a slot


90


is provided through the thickness of the handle to provide venting means. Additionally, the toothbrush


10




d


provides that the gripping portion


92


is generally oval which provides enhanced grip.





FIG. 17

shows a cross-sectional profile of a toothbrush


10




e


which is very much like any of the toothbrushes


10




a


-


10




d


already described, except that toothbrush


10




e


includes rubber grip portions


98


.




The toothbrush


10




f


shown in

FIG. 18

is very much like the toothbrush


10




a


shown in

FIGS. 1 and 2

(and FIGS.


3


-


10


), and includes bristles


32


and a rim


100


. However, unlike toothbrush


10




a


, toothbrush


10




f


provides that the bristles


32


are attached directly to the lower portion


42


, as opposed to being attached to a pad.




The toothbrush


10




g


shown in

FIG. 19

is very much like the toothbrush


10




a


shown in

FIGS. 1 and 2

(and FIGS.


3


-


10


), but instead of including a single longitudinal groove for venting, the toothbrush


10




g


includes three small ribs


102


on the top surface to prevent a build up of vacuum in a user's mouth.




With regard to use, use of toothbrushes


10




b


-


10




g


is very much the same as toothbrush


10




a.






While embodiments of the present invention are shown and described, it is envisioned that those skilled in the art may devise various modifications of the present invention without departing from the spirit and scope of the appended claims.



Claims
  • 1. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a bristle pack located in the recess with bristles attached by one end to a base of the recess, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess in the form of a supply line disposed among the bristles.
  • 2. A toothbrush as in claim 1, wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user.
  • 3. A toothbrush as in claim 2, wherein the air vent means is formed by at least one longitudinal groove on the handle, one end of which is in close proximity to the bristles and the other end of which is sufficiently distanced therefrom to ensure that it cannot be fouled by the mouth.
  • 4. A toothbrush as in claim 2, wherein the air vent means comprises a slot through a thickness of the handle.
  • 5. A toothbrush as in claim 2, wherein the air vent means comprises a plurality of ribs on a surface of the toothbrush.
  • 6. A toothbrush as in claim 1, wherein the handle includes a bend.
  • 7. A toothbrush as in claim 1, wherein the toothbrush includes structure configured to receive a placard.
  • 8. A toothbrush as in claim 7, wherein the structure configured to receive a placard comprises flanges which define a channel.
  • 9. A toothbrush as in claim 1, wherein the supply line is disposed centrally among the bristles.
  • 10. A toothbrush comprising a handle with a head portion, bristles attached to the head portion, a fluid supply line provided along or through the handle and communicating with the head portion in the form of a supply line disposed among the bristles, a vacuum supply line provided along or through the handle and communicating with the head portion, air vent means on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user.
  • 11. A toothbrush as in claim 10, wherein the air vent means is formed by at least one longitudinal groove on the handle, one end of which is in close proximity to the bristles and the other end of which is sufficiently distanced therefrom to ensure that it cannot be fouled by the mouth.
  • 12. A toothbrush as in claim 10, wherein the air vent means comprises a slot through a thickness of the handle.
  • 13. A toothbrush as in claim 10, wherein the supply line is disposed centrally among the bristles.
  • 14. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a pad located in the head portion, a bristle pack located in the recess with bristles attached by one end to the pad, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess in the form of a supply line disposed among the bristles.
  • 15. A toothbrush as in claim 14, wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user.
  • 16. A toothbrush as in claim 15, wherein the air vent means is formed by at least one longitudinal groove on the handle, one end of which is in close proximity to the bristles and the other end of which is sufficiently distanced therefrom to ensure that it cannot be fouled by the mouth.
  • 17. A toothbrush as in claim 15, wherein the air vent means comprises a slot through a thickness of the handle.
  • 18. A toothbrush as in claim 15, wherein the air vent means comprises a plurality of ribs on a surface of the toothbrush.
  • 19. A toothbrush as in claim 14, wherein the handle includes a bend.
  • 20. A toothbrush as in claim 14, wherein the toothbrush includes structure configured to receive a placard.
  • 21. A toothbrush as in claim 20, wherein the structure configured to receive a placard comprises flanges which define a channel.
  • 22. A toothbrush as in claim 14, wherein the supply line is disposed centrally among the bristles.
  • 23. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a bristle pack located in the recess with bristles attached by one end to a base of the recess, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means is formed by at least one longitudinal groove on the handle, one end of which is in close proximity to the bristles and the other end of which is sufficiently distanced therefrom to ensure that it cannot be fouled by the mouth.
  • 24. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a bristle pack located in the recess with bristles attached by one end to a base of the recess, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means comprises a slot through a thickness of the handle.
  • 25. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a bristle pack located in the recess with bristles attached by one end to a base of the recess, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means comprises a plurality of ribs on a surface of the toothbrush.
  • 26. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a pad located in the head portion, a bristle pack located in the recess with bristles attached by one end to the pad, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means is formed by at least one longitudinal groove on the handle, one end of which is in close proximity to the bristles and the other end of which is sufficiently distanced therefrom to ensure that it cannot be fouled by the mouth.
  • 27. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a pad located in the head portion, a bristle pack located in the recess with bristles attached by one end to the pad, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means comprises a slot through a thickness of the handle.
  • 28. A toothbrush comprising a handle with a head portion, a recess in the head portion of the handle, a pad located in the head portion, a bristle pack located in the recess with bristles attached by one end to the pad, an opening of the recess being bounded by inwardly directed shoulders of a rim, outer extremities of the bristles lying in abutting relationship with inner faces of the shoulders of the rim, and there being a fluid supply line provided along or through the handle and communicating with the recess; wherein air vent means are provided located on the handle and extending along the handle from a position in close proximity to the bristles to a position where it cannot be fouled by the mouth of the user; wherein the air vent means comprises a plurality of ribs on a surface of the toothbrush.
RELATED APPLICATION

This application is a continuation-in-part of U.S. patent application Ser. No. 09/509.370, filed Mar. 24, 2000, now U.S. Pat. No. 6,315,556 which was a national stage filing under 35 U.S.C. §371 of PCT/GB98/02811, filed Sep. 16, 1998, which International Application was published by the International Bureau in English on Apr. 1, 1999, and claimed the benefit of British patent application Serial No. 9720313.7, filed Sep. 25, 1997. The present application also claims tile benefit of United States provisional application Serial No. 60/268.260, filed Feb. 13, 2001.

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Provisional Applications (1)
Number Date Country
60/268260 Feb 2001 US
Continuation in Parts (1)
Number Date Country
Parent 09/509370 US
Child 09/955873 US