High efficiency electric toothbrush

Abstract

An electric toothbrush having a particular assembly, bristle configuration, and drive mechanism is disclosed. The assembly, bristle configuration, and drive mechanism are such that operation of the brush is highly efficient and more economical than currently known toothbrushes. Specifically, an electric toothbrush is disclosed comprising a body, a head, and a neck extending therebetween. The head utilizes one of several unique and preferred arrangements of static and movable bristles. The static bristles at least partially surround the collection of movable bristles which are provided on a movable bristle carrier. A motor and drive train impart motion to the collection of movable bristles. Also disclosed is a toothbrush having a simplified and improved assembly. The toothbrush includes a unique assembly utilizing a one-piece housing in combination with a movable bristle carrier that is engaged on a brush head of the toothbrush, and a stationary brush head tip which is secured thereto. The unitary housing reduces the number of components of the toothbrush and decreases manufacturing costs. The brush head tip may be replaced with other tips and allows a consumer to individually tailor the brush to provide a particular brushing configuration as desired.

We claim:  
     
         1 . A low energy consumption electric toothbrush comprising: 
 a housing assembly including a brush head, a handle, and a neck extending between said brush head and said handle, said housing defining a hollow interior cavity;    a movable bristle carrier disposed on said brush head;    a motor providing a powered rotating shaft, a drive gear affixed to said shaft, and a power source in electrical communication with said motor and disposed in said hollow interior cavity,    a crown gear rotatably supported in said hollow interior cavity and oriented such that the axis of rotation of said crown gear is perpendicular to an axis of rotation of said motor and said drive gear, said crown gear configured and engaged with said drive gear of said motor such that said crown gear completes one revolution for a number, from one to three, of revolutions of said motor, said crown gear including (i) a first cam member extending from a face of said crown gear, said first cam having a center offset from said axis of rotation of said crown gear and (ii) a second cam member extending from a face of said first cam member, said second cam member having an axis of rotation co-extensive with said axis of rotation of said crown gear;    a drive shaft having a first end and a second opposite end, said first end engaged with said first cam member and said second cam member of said crown gear, and said second end engaged with said movable bristle carrier;    a first plurality of bristles retained on said movable bristle carrier;    a second plurality of stationary bristles retained on said brush head;    wherein upon operation of said motor, said crown gear is rotated, thereby imparting a reciprocating motion to said drive shaft and to said movable bristle carrier disposed on said brush head.    
     
     
         2 . The electric toothbrush of  claim 1  wherein said crown gear completes one revolution for every two revolutions of said motor.  
     
     
         3 . The electric toothbrush of  claim 1  wherein said power source is a single AA battery.  
     
     
         4 . The electric toothbrush of  claim 1  wherein said motor operates at speed of from about 1500 RPM to about 3500 RPM.  
     
     
         5 . The electric toothbrush of  claim 4  wherein said motor operates at a speed of about 2500 RPM.  
     
     
         6 . The electric toothbrush of  claim 1  wherein said crown gear has from about 8 to about 40 gear teeth.  
     
     
         7 . The electric toothbrush of  claim 6  wherein said crown gear has about 20 gear teeth.  
     
     
         8 . The electric toothbrush of  claim 1  wherein upon operation of said motor, said movable bristle carrier exhibits a stroke length of from about 0.5 mm to about 5 mm.  
     
     
         9 . The electric toothbrush of  claim 8  wherein said stroke length is about 1.7 mm.  
     
     
         10 . The electric toothbrush of  claim 1  wherein said motor exhibits the following current draw characteristics: (i) about 0.3 amps without a load, and (ii) from about 0.4 amps to about 0.6 amps under a typical brushing load.  
     
     
         11 . The electric toothbrush of  claim 1  wherein said first end of said drive shaft provides a partially enclosed end defining an inward facing interior wall that engages said first cam of said crown gear, and further defines an oval shaped aperture that engages said second cam of said crown gear.  
     
     
         12 . The electric toothbrush of  claim 11  wherein said interior wall of said partially enclosed end defines an oval shaped region.  
     
     
         13 . The electric toothbrush of  claim 12  wherein said oval shaped aperture defined in said partially enclosed end of said drive shaft is oriented such that a major axis of said oval shaped aperture is parallel to a longitudinal axis of said drive shaft.  
     
     
         14 . The electric toothbrush of  claim 13  wherein said major axis of said oval shaped region defined by said interior wall of said partially enclosed end is perpendicular to said major axis of said oval-shaped aperture.  
     
     
         15 . An electric toothbrush comprising: 
 a housing including a handle and a brush head, said housing defining a hollow interior region;    a movable bristle carrier disposed on said brush head;    a first plurality of bristles supported and retained on said bristle carrier;    a second plurality of bristles supported and retained on said brush head;    an electric motor providing a rotating shaft and power source in selectable electrical communication with said motor, disposed in said hollow interior region defined in said housing;    a first drive gear affixed to said shaft of said motor;    a second gear engaged with said first gear and oriented such that the axis of rotation of said second gear is perpendicular to the axis of rotation of said first gear, said second gear including an offset member disposed radially outward from the center of said second gear;    a drive shaft extending between and coupling said bristle carrier with said offset member such that upon rotation of said second gear, a reciprocating motion is imparted to said bristle carrier;    wherein for every stroke cycle completed by said bristle carrier, said shaft of said motor rotates from one to three times, and during operation, and said motor operates at a speed of from about 1500 rpm to about 3500 rpm.    
     
     
         16 . The electric toothbrush of  claim 15  wherein said bristle carrier completes one stroke cycle for every two rotations of said shaft of said motor.  
     
     
         17 . The electric toothbrush of  claim 15  wherein said power source is a M battery.  
     
     
         18 . The electric toothbrush of  claim 15  wherein said motor operates at a speed of about 2500 rpm.  
     
     
         19 . The electric toothbrush of  claim 15  wherein said bristle carrier travels from about  0 .5 mm to about 5 mm in a first direction, and then another 0.5 mm to about 5 mm in an opposite direction during a stroke cycle.  
     
     
         20 . The electric toothbrush of  claim 19  wherein said distance is  1 . 7  mm in each direction.  
     
     
         21 . The electric toothbrush of  claim 15  wherein said offset member of said second gear includes: 
 a first cam member disposed on said second gear and providing a cam surface defined along a periphery of said first cam member, said first cam member having a center offset from said axis of rotation of said second gear; and  
 a second cam member disposed on said first cam member, said second cam member providing a cam surface defined along a periphery of said second cam member, said second cam member having a center co-extensive with said axis of rotation of said second gear.  
 
     
     
         22 . An electric toothbrush comprising: 
 a housing having a handle, a brush head, and a neck extending between said handle and said brush head, said housing defining a hollow interior cavity;    a bristle carrier movably disposed on said brush head;    a movable drive shaft coupled to said bristle carrier and movable therewith, said drive shaft extending within at least a portion of said hollow interior cavity defined in said housing;    a first plurality of bristles disposed on said carrier and movable therewith;    a motor and power source disposed in said hollow interior cavity defined in said housing, said motor providing a powered output shaft;    a gearing assembly disposed in said hollow interior cavity and engaged with said shaft of said motor and said drive shaft such that upon operation of said motor, a reciprocating motion is imparted to said drive shaft and said bristle carrier;    a second plurality of stationary bristles disposed on said brush head;    wherein said motor exhibits the following current draw characteristics: (i) about 0.3 amps without a load, and (ii) from about 0.4 amps to about 0.6 amps under a typical brushing load, said motor operates at a speed of from about 1500 rpm to about 3500 rpm.    
     
     
         23 . The toothbrush of  claim 22  wherein said power source consists of a AA battery.  
     
     
         24 . The toothbrush of  claim 22  wherein said movable bristle carrier exhibits a stroke length of from about 0.5 mm to about 5 mm.  
     
     
         25 . The toothbrush of  claim 22  wherein said motor operates at a speed of about 2500 rpm.  
     
     
         26 . A low energy consumption electric toothbrush comprising: 
 a housing assembly including a brush head, a handle, and a neck extending between said brush head and said handle, said housing defining a hollow interior cavity;    a movable bristle carrier disposed on said brush head;    a motor providing a powered rotating shaft, a drive gear affixed to said shaft, and a power source in the form of a single (AA) battery, said power source in electrical communication with said motor and disposed in said hollow interior cavity, said power source providing a voltage source of from about 0.9 volts to about 2.5 volts;    a crown gear rotatably supported in said hollow interior cavity and engaged with said drive gear of said motor, said crown gear including an offset member disposed radially outward from an axis of rotation of said crown gear;    a drive shaft having a first end and a second opposite end, said first end engaged with said offset member of said crown gear and said second end engaged with said movable bristle carrier;    a first plurality of bristles retained on said movable bristle carrier;    a second plurality of stationary bristles retained on said brush head;    wherein upon operation of said motor, said crown gear is rotated, thereby imparting a reciprocating motion to said drive shaft and to said movable bristle carrier disposed on said brush head, said toothbrush exhibiting a total run time upon application of a one (1) pound load to said first and second plurality of bristles on said brush head, of at least 100 minutes.    
     
     
         27 . The toothbrush of  claim 26  wherein said total run time is at least 120 minutes.  
     
     
         28 . The toothbrush of  claim 26  wherein said total run time is at least 140 minutes.  
     
     
         29 . The toothbrush of  claim 26  wherein said total run time is at least 160 minutes.  
     
     
         30 . The toothbrush of  claim 26  wherein said total run time is at least 180 minutes.  
     
     
         31 . The toothbrush of  claim 26  wherein said power source provides a voltage source of about 1.5 volts.  
     
     
         32 . The toothbrush of  claim 26  wherein upon operation, said movable bristle carrier reciprocates and exhibits a stroke length of from about 0.5 mm to about 5.0 mm.  
     
     
         33 . The toothbrush of  claim 26  wherein upon operation, said movable bristle carrier reciprocates and exhibits a stroke length of from about 1.0 mm to about 3.5 mm.  
     
     
         34 . The toothbrush of  claim 26  wherein upon operation, said movable bristle carrier reciprocates and exhibits a stroke length of from about 1.25 mm to about 2.5 mm.  
     
     
         35 . The toothbrush of  claim 26  wherein upon operation, said movable bristle carrier reciprocates and exhibits a stroke length of from about 1.5 mm to about 1.7 mm.  
     
     
         36 . An electric toothbrush comprising: 
 a housing having a brush head and a handle, said housing defining an interior hollow cavity;    a movable bristle carrier disposed on said brush head;    a power source in the form of a single (AA) battery disposed in said hollow cavity, said battery providing a voltage source of from about 0.9 volts to about 2.5 volts;    a motor in selective electrical contact with said power source, said motor disposed in said hollow cavity; and    a drive train disposed in said hollow cavity and engaged with said motor and said movable bristle carrier such that upon operation of said motor, said bristle carrier undergoes a reciprocating motion.    
     
     
         37 . The toothbrush of  claim 36  wherein said toothbrush exhibits a total run time upon application of a one (1) pound load, of at least 100 minutes.  
     
     
         38 . The toothbrush of  claim 36  wherein said total run time is at least 120 minutes.  
     
     
         39 . The toothbrush of  claim 36  wherein said total run time is at least 140 minutes.  
     
     
         40 . The toothbrush of  claim 36  wherein said total run time is at least 160 minutes.  
     
     
         41 . The toothbrush of  claim 36  wherein said total run time is at least 180 minutes.  
     
     
         42 . The toothbrush of  claim 36  wherein said movable bristle carrier exhibits a stroke length of from about 0.5 mm to about 5.0 mm.  
     
     
         43 . The toothbrush of  claim 36  wherein said movable bristle carrier exhibits a stroke length of from about 1.0 mm to about 3.5 mm.  
     
     
         44 . The toothbrush of  claim 36  wherein said movable bristle carrier exhibits a stroke length of from about 1.25 mm to about 2.5 mm.  
     
     
         45 . The toothbrush of  claim 36  wherein said movable bristle carrier exhibits a stroke length of from about 1.5 mm to about 1.7 mm.  
     
     
         46 . The toothbrush of  claim 36  wherein said motor operates at a speed of from about 1500 RPM to about 3500 RPM.