The invention relates generally to the field of oral care, and in particular to toothbrushes. More specifically, the invention relates to a brush head for a toothbrush.
U.S. Pat. No. 5,577,285 (the '285 patent) discloses an electric toothbrush with a rotary bristle supporting structure. In one embodiment of the invention shown in FIG. 6, the brush head is driven such that an outer ring of bristles 45a and an inner ring of bristles 45b are moved in an alternating rotary motion in opposite directions. While such an arrangement is beneficial for cleaning, for example, the bucal or lingual tooth surfaces, the lack of motion of any of the bristles in an up and down pattern results in a less than optimal cleaning of the inter-dental tooth surfaces.
FIG. 9 of the '285 patent discloses an additional embodiment of the invention in which all of the bristles 45 are rotated about an axis 54 while also being moved in an up and down motion parallel to this axis. This embodiment will provide enhanced cleaning of the inter-dental tooth surfaces. However, the fact that all of the bristles are moved up and down limits the depth of penetration that the bristles can obtain between the teeth. This is because while some of the bristles are trying to penetrate between the teeth, others are pressing against, for example, the bucal tooth surface, thus limiting the motion of the brush head towards the teeth.
The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to one aspect of the present invention, a head for an electric toothbrush, includes a first bristle support which is rotatable about an axis and a plurality of first bristles extending from the first bristle support. A second bristle support includes a plurality of second bristles extending from a surface of the second bristle support at an acute angle to the surface.
These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.
Beginning with
A pair of cam follower pins 22 are secured to opposite sides of the lower portion of core 20. Core 20 is positioned inside of a brush base 24 such that pins 22 are forced to ride along respective cam tracks 26 as well as respective vertical slider tracks 28 (one slider track is hidden behind the other). A retaining pin 30 rides in a track 32 to retain base 24 within a housing 34. A guide/rotation pin 36 passes through a hole in the bottom of housing 34 and is secured to base 24.
Operation of support 14 will be explained with reference to
In an alternative embodiment, all of bristles 16 are eliminated, leaving only probe 18 for cleaning teeth. This embodiment would be used primarily for cleaning interdental spaces, not for cleaning the other surfaces of teeth.
Turning to
A pivot 54 can rotate in a bearing hole 56 situated in front part 50 of tube 42. Pivot 54 is retained in hole 56 by a ring 58. A brush base 60 is press fitted onto pivot 54. Brush base 60 has holes 62 in which tufts of bristles 64 are secured. A cross pin 66 is welded onto the free end of pivot 54. Both ends of cross pin 66 retain brush base 60 on pivot 54 by interaction with a shoulder 68 of the brush base. The central part of cross pin 66 is placed in a bearing hole 70 of a rocker 72. Rocker 72 can swivel about cross pin 66 and contains holes 74 in which tufts of bristles 76 are secured.
Shaft 44 includes a bearing hole 78 in which a drive rod 80 can move. The distance between axis 52 of pin 46 and an axis 82 of drive rod 80 is a radius r1. A stud 84 is welded onto the free end of drive rod 80. The distance between an axis 86 of pivot 54 and an axis 88 of stud 84 is a radius r2. Stud 84 can move in a bearing seat 90 in brush base 60. At one end of stud 84 is carried a ball 92 which can move in a cylindrical slot 94 in rocker 72.
When shaft 44 is oscillated about axis 52 through an angle of +−alpha 1 about pin 46, two different motions are induced. First, brush base 60 and rocker 72 are oscillated in a rotating manner through an angle of +−beta 1 about pivot 54 in bearing hole 56. This oscillating rotation causes bristles 64 to wipe plaque off teeth like a broom. Second, rocker 72 is oscillated in a rotating manner through an angle of +−gamma 1 about cross pin 66 in bearing hole 70. Oscillation of rocker 72 about pin 66 causes bristle tufts 76 to loosen plaque like a chisel. Two cycles of oscillation of rocker 72 about pin 66 occur for every one cycle of oscillation of base 60 and rocker 72 about pivot 54. The relations between the oscillation angles alpha 1 to beta 1 and alpha 1 to gamma 1 depend only on radii r1 and r2.
Referring to
In the mid-position of the oscillating rotation of a shaft 100, a drive rod 102 is located at a distance e from a median plane 104 of a brushhead 106. A stud 108 is welded laterally on a free end of drive rod 102 with a distance e between the center-lines. Stud 108 is movable in a bearing seal 110 of a brush base 112. When a drive shaft 114 is in a mid-oscillation position, stud 108 is in a median plane 116 of brush base 112. Drive rod 102 can move in a bearing hole 118 in shaft 114. Bearing hole 118 is situated in the distance e from median plane 104 of shaft 114 when the shaft is in its mid-oscillation position.
When shaft 114 is oscillated about median plane 104 through an angle of +−alpha 1, two different motions are induced. First, brush base 112 and rocker 72 are oscillated in a rotating manner through an angle of +−beta 2 which is smaller than +−beta 1 about axis 120. Second, rocker 72 is oscillated in a rotating manner through an angle of +−gamma 2 which is bigger than +−gamma 1 about cross pin 66. The relations between the oscillation angles alpha 1 to beta 2 and alpha 1 to gamma 2 depend on radii r1 and r2 as well as on the distance e.
In embodiments 2 and 3 of the invention, one component of the rocking motion of rocker 72 causes bristles 76 to move up and down (i.e. substantially parallel to pivot 54) relative to bristles 64.
This application is a continuation of U.S. patent application Ser. No. 10/697,206 filed on Oct. 30, 2003 now abandoned which is a continuation of U.S. patent application Ser. No. 10/456,769 filed on Jun. 6, 2003 (U.S. Pat. No. 6,760,946) which is a continuation of U.S. patent application Ser. No. 09/425,423 filed Oct. 22, 1999 (U.S. Pat. No. 6,574,820).
Number | Name | Date | Kind |
---|---|---|---|
1392623 | Cheatham | Oct 1921 | A |
1896731 | Lippett | Feb 1933 | A |
1911973 | Ruse | May 1933 | A |
2140307 | Belaschk et al. | Dec 1938 | A |
3270360 | Kropp | Sep 1966 | A |
4156620 | Clemens | May 1979 | A |
4346492 | Solow | Aug 1982 | A |
4545087 | Nahum | Oct 1985 | A |
4766630 | Hegemann | Aug 1988 | A |
4845795 | Crawford et al. | Jul 1989 | A |
5007127 | Paolo | Apr 1991 | A |
5046213 | Curtis et al. | Sep 1991 | A |
5068939 | Holland | Dec 1991 | A |
5070567 | Holland | Dec 1991 | A |
5088145 | Whitefield | Feb 1992 | A |
5138734 | Chung | Aug 1992 | A |
5145369 | Lustig et al. | Sep 1992 | A |
5184368 | Holland | Feb 1993 | A |
5186627 | Amit et al. | Feb 1993 | A |
5226206 | Davidovitz et al. | Jul 1993 | A |
5259083 | Stansbury | Nov 1993 | A |
5301381 | Klupt | Apr 1994 | A |
5337435 | Krasner et al. | Aug 1994 | A |
5357644 | Theriault | Oct 1994 | A |
5365624 | Berns | Nov 1994 | A |
5416942 | Baldacci et al. | May 1995 | A |
5435032 | McDougall | Jul 1995 | A |
5446939 | Park | Sep 1995 | A |
5450646 | McHugh et al. | Sep 1995 | A |
5499420 | Boland | Mar 1996 | A |
5500970 | Maurer et al. | Mar 1996 | A |
5504959 | Yukawa et al. | Apr 1996 | A |
5524312 | Tan et al. | Jun 1996 | A |
5546626 | Chung | Aug 1996 | A |
5573020 | Robinson | Nov 1996 | A |
5577285 | Drossler | Nov 1996 | A |
5625916 | McDougall | May 1997 | A |
5652990 | Driesen et al. | Aug 1997 | A |
5709233 | Boland et al. | Jan 1998 | A |
5715556 | Chung | Feb 1998 | A |
5732433 | Gocking et al. | Mar 1998 | A |
5738575 | Bock | Apr 1998 | A |
5778474 | Shek | Jul 1998 | A |
5836030 | Hazeu et al. | Nov 1998 | A |
5839148 | Volpenhein | Nov 1998 | A |
5850655 | Gocking et al. | Dec 1998 | A |
5974615 | Schwarz-Hartmann et al. | Nov 1999 | A |
6032313 | Tsang | Mar 2000 | A |
6106290 | Weissman | Aug 2000 | A |
6574820 | DePuydt et al. | Jun 2003 | B1 |
6760946 | DePuydt et al. | Jul 2004 | B2 |
6889401 | Fattori et al. | May 2005 | B2 |
Number | Date | Country |
---|---|---|
330411 | Apr 1998 | CN |
4412301 | Oct 1995 | DE |
29517610 | Apr 1997 | DE |
19803311 | Aug 1999 | DE |
0488971 | Jun 1992 | EP |
9-294631 | Nov 1997 | JP |
10-66704 | Mar 1998 | JP |
H10-66704 | Mar 1998 | JP |
WO 9428823 | Dec 1994 | WO |
WO 0078244 | Dec 2000 | WO |
Number | Date | Country | |
---|---|---|---|
20070006403 A1 | Jan 2007 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 10697206 | Oct 2003 | US |
Child | 11430280 | US | |
Parent | 10456769 | Jun 2003 | US |
Child | 10697206 | US | |
Parent | 09425423 | Oct 1999 | US |
Child | 10456769 | US |