Tooth brush with removable brush head

A tooth brush with a handle portion in the shape of a bent trapezoid and a head portion affixed thereto, and a latch mechanism to affix two items to each other. The tail region is affixed to one end of the main body region and angled upward with respect to the main body region. The "S" shaped region is affixed to the other end of the main body region with an upper and a lower curved indentation to form the "S". The surfaces of the "S" shaped region that form the "S" are extensions of the top and bottom surfaces of the main body region. Finally, the head portion is affixed to the proximate end of the "S" shaped region, with the head portion having bristles affixed thereto in a selected pattern. The latching mechanism for affixing a first item to a second item includes a male latching portion affixed to the first item, and a cavity defined within the second item disposed to receive the male latching portion. The male latching portion includes a "U" shaped body with the top of each leg of the " U" being affixed to, and extending outward from, the surface of the end of the first item that is to abut the surface of the end of the second item when the first item is affixed to the second item. The male latching portion also includes a spring finger having one end thereof affixed to the same surface to which the legs of the "U" shaped body are affixed and extends outward therefrom between the legs of the "U" shaped body. The spring finger has at its other end a locking tooth that extends outward from between the legs of the "U" shaped body to be captured within the cavity of the second item.

BACKGROUND OF THE INVENTION 
The present invention relates to tooth brushes having a handle to allow the 
user to have positive control of the brushing action while being used with 
either the right or the left hand, and more particularly to tooth brushes 
having a replaceable brush head when the bristles have worn down. 
The prior art includes numerous tooth brushes with various bristle 
orientations, head angles, and other appliances attached to the handle of 
the tooth brush. Additionally, there is a tooth brush sold under the name 
"RADIUS" that has a handle that is shaped to provide positive control of 
the use of the brush, however, the handle design of that brush is such 
that there is a right hand model and a left hand model. The bristle layout 
of this brush is in the shape of an oval which does not provide a good 
cleaning action when the brush is used. Further, no tooth brush is known 
to have a replaceable head. 
It would be desirable to have a tooth brush that provides for positive 
control of the brushing action by means of a handle that is designed to be 
comfortably held by the user in any way that suits him regardless of which 
hand he uses. In addition, it would be desirable to have replaceable heads 
for the tooth brush to minimize disease transmission and the cost of the 
brush to the consumer. The present invention provides such a tooth brush 
design. 
SUMMARY OF THE INVENTION 
In accordance with the illustrated embodiments, the present invention 
provides a tooth brush with a handle portion in the shape of a bent 
trapezoid and a head portion affixed thereto, and a latch mechanism to 
affix two items to each other. The tooth brush includes a handle portion 
with a main body region, a tail region and an "S" shaped region. The main 
body region is substantially rectalinear in shape with a length that is 
several times longer than either its height or width. In addition, the 
main body region defines a top, a bottom and two side surfaces. The tail 
region is affixed to one end of the main body region and angled upward 
through a selected angle with the top surface of the main body region. The 
"S" shaped region is affixed to the other end of the main body region with 
an upper and a lower curved indentation to form the "S". The surfaces of 
the "S" shaped region that that form the "S" are extensions of the top and 
bottom surfaces of the main body region. Finally, the head portion is 
affixed to the distal end of the "S" shaped region, with the head portion 
having bristles affixed thereto in a selected pattern. 
The latching mechanism for affixing a first item to a second item includes 
a male latching portion affixed to the first item, and a cavity defined 
within the second item disposed to receive the male latching portion on 
the first item. The male latching portion includes a "U" shaped body with 
the top of each leg of the "U" being affixed to, and extending outward 
from, the surface of the the end of the first item that is to abut the 
surface of the end of the second item when the first item is affixed to 
the second item. The male latching portion also includes a spring finger 
having one end thereof affixed to the same surface to which the legs of 
the "U" shaped body are affixed and extends outward therefrom between the 
legs of the "U" shaped body. The spring finger has at its other end a 
locking tooth that extends outward from between the legs of the "U" shaped 
body.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The present invention is an ergonomically designed tooth brush which 
provides positive control during brushing while being comfortable to grasp 
in numerous ways with either hand. In addition, the head is designed to be 
removable when the bristles wear down to minimize the replacement cost of 
the brush. 
Referring to FIGS. 1a-e there are shown several views of the tooth brush 10 
of a first embodiment of the present invention, and in FIG. 1f there are 
shown the cross-sectional shapes of the handle and head at several points 
along its length. From these views it can be seen that the handle is a 
bent trapezoid which is substantially rectangular in cross-section 
throughout its length. To improve the comfort when the handle is grasped, 
the corners of the surface of the handle, both radially and axially, are 
rounded. 
Tooth brush 10 has a head portion 12 and a handle portion 14. Head 12 is 
removably affixed to handle portion 14 to permit the replacement of head 
portion 12 when the bristles are worn or bacterially infected. 
Additionally, handle portion 14 has three regions: a main body region 18, 
a tail region 16 and an "S" shaped region 20. As shown, the head portion 
12 attaches to proximate end of the "S" shaped region 20 of the handle 
portion, which is next followed by the main body region 18 and then the 
tail region 16. From FIG. 1b it can be seen that the radius of curvature 
of the bristle side of the "S" shaped region 20 is approximately 3.5 times 
the radius of curvature of the other side of the "S" shaped region 20. 
Those two indentations are provided to accommodate the thumb and 
forefinger of the user, and it is those indentations, when the tooth brush 
is grasped thereby, that provide the control of the brush during usage. 
Also, in FIG. 1b it can be seen that the tail region 16 turns upward with 
respect to the bristle side of head 12, as does head 12 unlike the prior 
art which turns downward. 
In FIG. 1a it can further be seen that the "S" shaped region 20, when 
viewed from the top or bottom, has a slight hour glass shape as a result 
of indentations 22. Indentations 22 are also provided to accommodate the 
thumb and forefinger of the user to control the brush in use, when so 
held. The main body region 18 and the tail region 16 are provided to 
accommodate the other three fingers of the user when the tooth brush 10 is 
being used. Additionally, the tail region 16 is approximately 12% of the 
overall length of the tooth brush 10 of the present invention and may or 
may not be contacted during use depending on the way that the user chooses 
to hold tooth 10 during use thereof. 
A second embodiment of the tooth brush of the present invention is shown in 
FIGS. 6a-c. The differences between this embodiment and the first 
embodiment are only in the outline shape of the head portion 12' and tail 
region 16'. Head portion 12' has a rounded forward end instead of a 
squared off forward edge as in head portio 12. Additionally, head 12' does 
not neck down behind the bristles as does head portion 12. The distal end 
of tail region 16' is also curved instead of substantially square as in 
tail region 16. Otherwise tooth brush 14' is the same as tooth brush 14. 
Referring next to FIGS. 2a-d there is shown four ways of holding tooth 
brush 10 with the right hand. For ease of viewing the accommodation of the 
users fingers 26-32 and thumb 24 as they grasp the handle portion 14, only 
the portion of the fingers 26-32 and thumb 24 were they contact the handle 
portion 14 are shown. In FIG. 2a the thumb 24 and the forefinger 26 are 
contacting the large and small radius of curvature sections, respectively, 
of the "S" shaped region 20 of tooth brush 10, with the other fingers 
28-32 being accommodated by the main body region 18 and tail region 16. 
In FIG. 2b the thumb 24 and forefinger 26 are grasping the "S" shaped 
region 20 on opposite sides in indentations 22, with the other fingers 
28-32 being accommodated by the main body region 18 and tail region 16. 
In FIG. 2c thumb 24 is in contact with the back of "S" shaped region 20 
forward of the smaller radius of curvature indentation and forefinger 26 
is in contact with one of indentations 22 and extents beneath the "S" 
shaped region to make contact with the large radius of curvature 
indentation on the bottom of handle portion 14. The other fingers 28-32 
are, in this view, accommodated by the side of main body region 18 and 
tail region 16. 
In FIG. 2d thumb 24 is contacting the small radius of curvature section of 
the "S" shaped region 20 of tooth brush 10, with fingers 26-32 being 
accommodated by the main body region 18 and tail region 16. 
Note, the above-described ways of grasping tooth brush 10 are presented as 
illustrative of the ways that it can be grasped and are not intended to be 
the only ways. Additionally, tooth brush 10 can be grasped by the left 
hand in the same ways as illustrated in each of FIGS. 2a-d. To make those 
figures illustrative of left handed grasping of tooth brush 10, one need 
only make mirror images of them. 
Details of the latching mechanism between the head portion 12 and the 
handle portion 14 are shown in FIGS. 3-5. The male latch portion is 
affixed to head portion 12 and the cavity for receiving same is defined in 
the end of the handle portion 14. FIGS. 3a-b, 4 and 5b each shows a view 
of the male latch portion. FIG. 5a shows details of the cavity in the end 
of the handle portion 14 for receiving the male latch portion, and FIGS. 
5c and d illustrate the mating and the release of the latch. While the 
latching mechanism herein is described as being for the mounting of a 
removable tooth brush head to a specially design tooth brush handle, it is 
not intended that this latching mechanism can only be utilized for tooth 
brushes. The latching mechanism disclosed herein can be utilized in any 
situation where a firm, yet temporary, attachment is desired. 
The male latch portion includes "U" shaped body 34 that has the top of each 
leg of the "U" attached to the end of the head portion 12 that abuts the 
handle portion 14 when it is mounted thereto. Within the opening of the 
"U" there is a spring finger 38 having one end affixed to the same surface 
of head portion 12 as is the "U" shaped body 34. The free end of spring 
finger 38 turns downward forming a locking tooth 40. The lower surface of 
locking tooth 40 is inclined which is shortest furthest from the attached 
end of spring finger 38. Additionally, affixed to the center of the "U" 
shaped body 34 at the furthest extent from, and extending away from, head 
portion 12 is a key 36. 
Referring next to FIG. 5a there is shown a partial cut-away side plan view 
of the latch receiving cavity 42 in the end of handle portion 14. It can 
be seen that cavity 42 defines a space shaped to receive the male latch 
portion. Cavity 42 includes a ramp 44 up which the lower sloped face of 
locking tooth 40 advances as the male latch portion is inserted into 
cavity 42. When fully inserted, locking tooth 40 snaps into recess 52 when 
key 36 is fully seated into the distal end 48 of cavity 42. In 
communication with recess 52 from the lower surface of handle portion 14 
is a channel 46 for use when the male latch portion is to be released from 
cavity 42. 
In FIG. 5c the male latch portion is partially inserted into cavity 42 with 
key 36 in alignment with end 48 and the lower face of tooth 40 in contact 
with ramp 44. In FIG. 5d the male latch portion is shown fully inserted 
into cavity 42 with key 36 in end 48 and locking tooth 40 captured by 
recess 52. Additionally, FIG. 5d illustrates the method for releasing the 
male latch portion from cavity 42. This is accomplished by inserting key 
36 of a second male latch portion into channel 46 to push locking tooth 40 
inward to release it from recess 52. 
From the forgoing description, it will be apparent that the invention 
disclosed herein provides novel and advantageous tooth brush and latching 
mechanism designs. As will be understood by those familiar with the art, 
the invention may be embodied in other specific forms without departing 
from the spirit or essential characteristics thereof.