Patent Publication Number: US-6704965-B2

Title: Toothbrush with removable brushing members

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to toothbrushes, and in particular to a toothbrush with removable brushing members. 
     2. Description of the Related Art 
     Toothbrushes are commonly manufactured including a handle and a brush head where the brush head holds bristles or tufts of bristles suitable for cleaning teeth. Typically, the bristles are moved against the teeth in a sawing motion to remove plaque and other materials. When the bristles wear or become too soft to be able to use for cleaning effectively, the toothbrush is discarded and replaced with a new toothbrush. This practice is wasteful as the bristles typically wear out long before the handle or the brush head of the toothbrush will. U.S. Pat. No. 6,145,152 discloses a toothbrush with a replaceable head construction. In such a toothbrush, the head of the toothbrush can be replaced without replacing the brush handle. Nonetheless, an individual has to purchase a new brush head when only the bristles are wore out. 
     In some countries, toothbrushes are not commonly used and other means for dental cleaning are employed. For example, in Saudi Arabia, a piece of soft wood, commonly known as sywack, is used by an individual to clean the teeth. Sywack, also referred to as siwak or sewak, is a soft wood containing fine fibers running along the length of the wood. The user holds a sywack stick in a hand and rubs an end of the stick against the teeth for cleaning the surface of the teeth. Unfortunately, when the sywack stick is used, only the front surface of the front teeth (i.e., the incisors and the canines) can be directly approached by the end of the sywack stick. The side and back teeth (i.e., the bicuspids and the molars) and the inside surface of the front teeth receive less cleaning because of the difficulties in placing the cleaning surface of the sywack stick adjacent to these areas. Accordingly, a solution is needed to allow a user to use sywack in a way that will effectively clean all tooth surfaces of both the front and the back teeth in an individual. 
     SUMMARY OF THE INVENTION 
     According to the present invention, a toothbrush with removable brushing members is disclosed. The toothbrush includes a handle, a brush head extending from the handle, and a first brushing member of soft wood. The brush head includes a bottom surface and a body together defining a cavity for receiving the first brushing member. The brush head further includes an anchoring member extending partially around the inside perimeter of the body except at a first end of the inside perimeter of the body. The first brushing member is inserted into the cavity at the first end and is slid along the cavity into the anchoring member. The anchoring member compresses against and bites into the sides of the first brushing member to secure the first brushing member in the cavity. In one embodiment, the toothbrush includes multiple brushing members. 
     In one embodiment, the brushing members are stubs made of siwak sticks. A siwak stick can be cut into stubs of a desired height and assembled into the toothbrush of the present invention so that effective dental cleaning can be carried out using siwak. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a toothbrush with removable brushing members according to one embodiment of the present invention. 
     FIG. 2 is a side view of the toothbrush of FIG.  1 . 
     FIG. 3 is an enlarged perspective view of the brush head of the toothbrush of FIG. 1 according to one embodiment of the present invention. 
     FIG. 4 is a cross-sectional view of the brush head of the toothbrush of FIG. 3 including a brushing member according to one embodiment of the present invention. 
     FIGS. 5 a - 5   i  illustrate the process of assembling the brushing members in the brush head of FIG. 3 according to one embodiment of the present invention. 
     FIGS. 6 a - 6   i  is a top view of the toothbrush of the present invention illustrating the process of loading up to three pieces of sywack stubs into the brush head of the toothbrush. 
     FIG. 7 is a perspective view of a toothbrush with removable brushing members according to one embodiment of the present invention. 
     FIG. 8 is a top view of the toothbrush of FIG.  7 . 
     FIG. 9 is an enlarged perspective view of a brushing member used in the toothbrush of FIG.  7 . 
     FIG. 10 is a cross-sectional view of the brush head of FIG. 7 including a brushing member according to one embodiment of the present invention. 
     FIG. 11 is a cross-sectional view of the brush head of FIG. 7 including a brushing member according to another embodiment of the present invention. 
     FIGS  12   a - 12   c  are perspective views of a toothbrush with removable brushing members and a hinged bar as looking member according to one embodiment of the present invention. 
     FIG. 13 is a cross-sectional view of the brush head of a toothbrush including a concave bottom surface according to one embodiment of to present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     While certain embodiments of this invention will be described, it should be understood that this description is illustrative only and not limiting. Other embodiments of this invention will be obvious in view of the following disclosure. 
     FIG. 1 is a perspective view of a toothbrush  10  with removable brushing members according to one embodiment of the present invention. In accordance with the present invention, fully assembled toothbrush  10  includes removable and disposable brushing members  16   a - 16   c  which are inserted into the toothbrush during assembly. The brushing members are replaced when the bristles of the brushing members become worn out or too soft for effective cleaning. In this manner, the useful life of toothbrush  10  can be extended to provide a cost effective toothbrush. 
     Referring to FIG. 1, toothbrush  10  includes a handle  12  and a brush head  14  extending from handler  12 . Brush head  14  includes an elongated cavity for securing one or more brushing members in the cavity. The cavity can be provided with different dimensions for receiving brushing members having different diameters. In the present embodiment, the cavity has a width suitable for accommodating one brushing members and a length suitable for accommodating three brushing members  16   a - 16   c  and a locking member  16   d , arranged linearly along the length of the cavity of brush head  14 . In the present embodiment, locking member  16   d  is used to hold brushing members  16   a - 16   c  affixed in cavity  20  and locking member  16   d  has a height shorter than brushing members  16   a - 16   c . Of course, in other embodiments, locking member  16   d  can have the same height as the brushing members and thus, locking member  16   d  also functions as a brushing member. FIG. 2 illustrates a side view of toothbrush  10  illustrating the relative height of brushing members  16   a - 16   c  to locking member  16   d  in the present embodiment. The distal ends of brushing members  16   a - 16   c  are the cleaning surfaces for used in brushing against the teeth of a user. 
     Brushing members  16   a - 16   c  are typically cylindrical in shape and can be made of any material that is soft and suitable for brushing against the teeth. In the preferred embodiment of the present invention, brushing members  16   a - 16   c  are made of the soft wood sywack (also called siwak). Sywack or siwak is preferable as it is a natural material and is low cost. Sywack has been known to be effective for cleaning teeth as sywack contains fine fibers which fibers can be softened when wet. Furthermore, sywack contains a powder which is also known to be effective in teeth cleaning and in promoting healthy gum. In another embodiment, the brushing members can be made of bristles of nylon filaments, as will be described in more detail below. 
     In accordance with the preferred embodiment of the present invention, a piece of sywack is cut into stubs having substantially equal height. The sywack stubs are inserted into brush head  14  to assemble toothbrush  10 . Often, the bark or shell of the sywack stubs near the distal end of the stubs is shaved to expose the fibers. The process of assembling toothbrush  10  will be described in more detail below. Brushing members  16   a - 16   c  can have any desirable height and in the present embodiment, the height of the brushing members is approximately 12 mm. The height of the locking member can be approximately 5 mm. When sywack is used as the brushing members, the diameter of a sywack is typically 5-10 mm. Of course, brush head  14  can be designed to accommodate brushing members having different diameters. 
     FIG. 3 is a perspective view of brush head  14  of toothbrush  10  according to one embodiment of the present invention. In FIG. 3, brush head  14  is shown without any brushing members to illustrate the construction of the brush head in the present embodiment. Brush head  14  includes a body  18  and a bottom surface  19  defining a cavity  20  for accommodating one or more brushing members. In the present embodiment, brushing members  16   a - 16   c  are placed in cavity  20  against bottom surface  19  and are secured in the cavity of brush head  14  by a flange  22  formed around the inside perimeter of body  18 , except at an opening  24  at the base of brush head  14 . In accordance with the present embodiment, flange  22 , functioning as an anchoring member, engages the outside surfaces of the brushing members, thereby anchoring and securing the brushing members in place. Specifically, when the brushing members are made of sywack, flange  22  presses against the sides of the sywack stubs to secure the sywack stubs in cavity  20 . Opening  24  in brush head  14  is provided for inserting the brushing members before the brushing members are pushed towards flange  22  during the assembly process, as will be described in more detail below. 
     FIG. 4 is a cross-sectional view of brush head  14  according to one embodiment of the present invention. As shown in FIG. 4, flange  22 , disposed around the inside perimeter of body  18 , is provided with sufficient amount of protrusion such that flange  22  can bite into a brushing member  16  for securing the brushing member in the cavity. Typically, flange  22  is formed as a sharp notch or a sharp protrusion and is placed near the middle point along the height of body  18 . Of course, the shape of flange  22  is not critical as long as it provides sufficient compressive force for anchoring the brushing members in place. In the present embodiment, flange  22  is used as the anchoring member to anchor the brushing members in cavity  20 . However, one of ordinary skill in the art would appreciate that other anchoring mechanisms can be used for anchoring brushing members in the cavity of the brush head of the toothbrush of the present invention. For example, a spring-loaded mechanism around the inside perimeter of the brush head can be used to anchor the brushing members. 
     Handle  12  and brush head  14  of toothbrush  10  can be made of the same material or can be made of different materials. Typically, handle  12  and brush head  14  are made of a very hard wood or a conventional plastic material suitable for use in toothbrushes. When brush head  14  is made of wood, flange  22  can be formed in body  18 . When brush head  14  is made of plastic, flange  22  can be formed using an injection molding process. Flange  22  needs to be made with a material rigid enough to press against the brushing members so as to secure the brushing members in place. 
     The process of assembling toothbrush  10  of the present invention will now be described with reference to FIGS. 5 a  to  5   i  and FIGS. 6 a  to  6   i . FIGS. 5 a  to  5   i  illustrate the process of assembling the brushing members in brush head  14  of FIG. 3 according to one embodiment of the present invention. FIGS. 6 a  to  6   i  illustrate the same process from a top view of toothbrush  10 . As described above, when sywack stubs are used in toothbrush  10  of the present invention, in preparing the brushing members for assembly, the bark or shell of the sywack stubs at the distal ends of the stubs is often shaved to expose the fibers of the sywack stubs. 
     Beginning with FIG. 5 a,  a user inserts the first brushing member (denoted member  16   a ) into cavity  20  of brush head  14  at opening  24 . Because opening  24  is clear of any protrusion limiting the width of the opening, brushing member  16   a  can be easily inserted into cavity  20 . Then, the user slides brushing member  16   a  down towards the top of cavity  20 , allowing flange  22  to bite into the sides of brushing member  16   a  (FIG. 5 b ). The first brushing member is in place when it is slid to the top end of cavity  20  (FIG. 5 c ). Then, the user inserts a second brushing member (member  16   b ) at opening  24  as shown in FIG. 5 d.  Again, the user slides brushing member  16   b  towards the top end of cavity  20  (FIG. 5 e ) until the second brushing member is adjacent the first brushing member (FIG. 5 f ). Finally, the user inserts the last brushing member (member  16   c ) into opening  24  (FIG. 5 g ) and slides brushing member  16   c  towards the second brushing member  16   b  (FIG. 5 h ). In the present embodiment, brush head  14  is designed to accommodate three brushing members. Of course, the length of brush head  14  can be adjusted accordingly to accommodate any number of brushing members. Typically, one to three brushing members are desirable. 
     After all of the brushing members are in place, a locking member  16   d  is inserted into opening  24  to hold brushing members  16   a - 16   c  in place. In this manner, brushing members  16   a - 16   c  are secured in place and will not move when toothbrush  10  is used for cleaning teeth. In the present embodiment, locking member  16   d  is made of the same material as brushing members  16   a - 16   c  but is made with a shorter height than the brushing members. For example, when brushing members  16   a - 16   c  are sywack stubs, locking member  16   d  can be a sywack stub having reduced height. In an alternate embodiment, locking member  16   d  can have the same height as the brushing members and thus also functions as a brushing member. 
     When assembled as shown in FIGS. 5 i  and  6   i , toothbrush  10  can then be used to clean the teeth of a user as in a conventional fashion. The user holds onto handle  12  and place the cleaning surfaces (the distal ends) of brushing members  16   a - 16   c  adjacent the surface of the teeth. By applying a sawing motion, toothbrush  10  can be used to clean all exposed surfaces of the teeth effectively, including the inside surface of the teeth and the top surface of the molars. 
     The toothbrush of the present invention is particularly useful in Middle Eastern countries such as Saudi Arabia and Egypt where sywack are traditionally used for teeth cleaning. By using sywack stubs as the brushing members, the toothbrush of the present invention preserves the traditional cleaning materials used in those countries while giving the users the ability to clean all surfaces of all teeth effectively. Thus, a user may use the toothbrush of the present invention assembled with sywack stubs as brushing members to clean the front and back surfaces of the front, side and back teeth (i.e., the incisors, the canines, the bicuspids and the molars). Furthermore, using the toothbrush of the present invention, the user can also apply the cleaning surfaces of the sywack stubs to the top surfaces of the molars for effectively cleaning of all surfaces of all teeth. 
     In typical applications, after assembly of the sywack stubs in toothbrush  10 , toothbrush  10  can be immersed in water for about five minutes to rewet the sywack stubs. The rewetting process is particularly useful when the sywack stubs are made from dried sywack stick. The rewetting process makes the fibers in the sywack stubs tender and more flexible for the purpose of teeth cleaning. 
     In the present embodiment, toothbrush  10  uses a locking member  16   d  to hold brushing members  16   a - 16   c  affixed in cavity  20 . In an alternate embodiment of the present invention, a hinged bar or a brace or other locking mechanism can be used to retain the brushing members in plane. For example, a hinged bar  26  can be placed at the base of cavity  20  and is forced down in place against the last brushing members in cavity  20 , as shown in FIGS. 12 a - 12   c.  Alternately, a brace can be used to retain the brushing members in place. One of ordinary skill in the art would appreciate that a number of locking mechanisms can be used to secure the brushing members in toothbrush  10  of the present invention. In one embodiment, toothbrush  10  can be made with only one brushing member and without a locking member. The brushing member can be held in place by the flange in the brush head or by other suitable locking mechanism. 
     FIGS. 7-10 illustrate another embodiment of the present invention where the brushing members are made of nylon filaments. FIG. 7 is a perspective view of toothbrush  30  including removable brushing members  36   a  to  36   c  while FIG. 8 is a top view of toothbrush  30 . Brushing member  36  represents any one of brushing members  36   a  to  36   c  and includes a base  38  and multiple bristle tufts  37  extending from base  38 . The bristle tufts are typically made of nylon filaments or other conventional material used in making bristles for toothbrushes. Toothbrush  30  may include one or more brushing members. In toothbrush  30 , a locking member  39  is included for holding brushing members  36   a  to  36   c  affixed in the cavity of brush head  34 . As shown in FIGS. 7 and 8, locking member  39  can be made of the same material and can be of the same size as base  38  of brushing member  36 . 
     FIG. 9 is an enlarged perspective view of brushing member  36  used in toothbrush  30  of FIG.  7 . In the present embodiment, brushing member  36  is shown as including a square of  36  tufts of nylon filament bristles. The tufts are spaced apart at a suitable distance to provide effective cleaning capability. Base  38  of brushing member  36  can be made in wood or plastic or other conventional material rigid enough to secure bristle tufts  37 . In the embodiment shown in FIG. 9, base  38  includes a groove  40  for engaging the anchoring member, such as a flange, around the perimeter of brush head  34 . FIG. 10 is a cross-sectional view of brush head  34  including a brushing member  36 . Groove  40  of base  38  is disposed to engage flange  42  of brush head  34  for anchoring brushing member  36  in place. 
     FIG. 11 illustrates another embodiment a toothbrush of the present invention. In the embodiment shown in FIG. 11, brushing member  46  is similar in construction to brushing member  36  and includes multiple bristle tufts  47  and a base  48 . However, in the present embodiment, base  48  of brushing member  46  includes a protusion or a flange  49  along the sides of the base which is provided to engage with a groove  50  provided in brush head of the toothbrush. In this manner, brushing member  46  can be anchored in place by fitting flange  49  into groove  50  of the brush head. 
     In the present embodiment, toothbrush  30  uses locking member  39  for holding brushing members  36   a - 36   c  in place. In other embodiments, locking member  39  is not needed and brush head  34  can include other means for locking the brushing members in place. In an alternate embodiment, a spring loaded notch is provided at the base of brush head  34 . The brushing members are snapped in place by being forced downward into the cavity  20  through the notch. In yet another alternate embodiment, a resilient metal lever can be provided at the base of brush head  34  and the brushing members are snapped into the cavity of the brush head, after which the metal lever springs back in shape, holding the brushing members affixed in the cavity of the brush head. 
     The above detailed descriptions are provided to illustrate specific embodiments of the present invention and are not intended to be limiting. Numerous modifications and variations within the scope of the present invention are possible. For example, the bottom surface of the brush head can be shaped suitably, such as curved in a concave shape as shown in FIG. 13, for securing the brushing members. The present invention is defined by the appended claims.