CA2374083A1 - Electric toothbrush - Google Patents

Electric toothbrush Download PDF

Info

Publication number
CA2374083A1
CA2374083A1 CA002374083A CA2374083A CA2374083A1 CA 2374083 A1 CA2374083 A1 CA 2374083A1 CA 002374083 A CA002374083 A CA 002374083A CA 2374083 A CA2374083 A CA 2374083A CA 2374083 A1 CA2374083 A1 CA 2374083A1
Authority
CA
Canada
Prior art keywords
drive shaft
electric toothbrush
output shaft
camwheel
shaft
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
CA002374083A
Other languages
French (fr)
Inventor
Paul Bernhardt Specht
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Unilever PLC
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of CA2374083A1 publication Critical patent/CA2374083A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61CDENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C17/00Devices for cleaning, polishing, rinsing or drying teeth, teeth cavities or prostheses; Saliva removers; Dental appliances for receiving spittle
    • A61C17/16Power-driven cleaning or polishing devices
    • A61C17/22Power-driven cleaning or polishing devices with brushes, cushions, cups, or the like
    • A61C17/40Power-driven cleaning or polishing devices with brushes, cushions, cups, or the like orbiting, e.g. nutating

Landscapes

  • Health & Medical Sciences (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Brushes (AREA)
  • Transmission Devices (AREA)

Abstract

An electric toothbrush is provided which includes an elongate body having an interior cavity, a power source mounted within the cavity, an elongate drive shaft driven rotatably by the power source, a camwheel mounted on the drive shaft, a yoke with projecting arms which confine travel of the camwheel, a crankshaft section driven by the drive shaft, an output shaft axially aligne d to the drive shaft, and a collar with a guide track eccentrically coupling t he crankshaft section to the output shaft thereby imparting both lateral and rotary reciprocating motion to the output shaft. A brushhead mounted on the front end of the elongate body accepts the motion from the output shaft. The mechanical drive system is fully enclosed within the housing of the elongate body. Brushheads are replaceably mountable outside the cavity on the front e nd.

Description

ELECTRIC TOOTHBRUSH
The invention concerns an electric toothbrush which operates a brushhead with three dimensional stroke movement.
Electric toothbrushes have been in development for over sixty years. The earliest type were relatively simple, electro-mechanical versions of manual toothbrushes with limited back-and-forth movement. More recent developments have featured enhanced performance batteries and high efficiency miniaturized electric motors. Today battery powdered electric toothbrushes figure prominently in the general product classification.
Yet with these drive train improvements, the basic electro-mechanical arrangement differs little from the earliest devices marketed. Essentially, the typical product consists of a battery, either rechargeable or replaceable, adjacent end to end to a small high speed electric motor. A drive shaft operated by the motor may in turn either be coupled to a mechanical drive train with reduction gears or crank arms or may be coupled with simple direct drive.
Most mechanical designs involve an oscillating fixed bristle array brush operating with a narrow back and forth angular range of rotary motion. Travel is essentially in a two dimensional plane. Various types of mechanical devices such as gears with levers, in combination or separately, deliver the rotary motion. In some instances, the brushhead may feature individually rotatable brush bundles driven by gearing alone. A third category of electric brush incorporates ultrasonic technology, either alone or in combination with an oscillating brush.
Among the considerable volume of literature is U.S. Patent 5,577,285 (Drossler) which describes an electric toothbrush in which a rotary shaft translates to a bristle supporting structure an alternating or a rotary motion. U.S. Patent 5,467,494 (Muller et al.) describes a mechanism with a pair of mutually pivotable parts, the first serving as a handle and the second a brushhead. A spring arranged between the parts snaps when a given pressure threshold is exceeded and resumes its original position when the pressure is decreased. Angular rotation is imparted by the spring action. U.S. Patent 4,276,672 (Teague, Jr. et al.) reports a water powered nutating system effectuating a rotary motion which in turn converts to an orbital motion in the brush working element. U.S. Patent 3,538,530 (Stemme) provides a motor-driven toothbrush based on a guide arrangement with cam faces with an outline resembling a figure eight. The guide shifts that portion of a brush stem extending into the housing. Thereby the entire brush operates along a path resembling the figure eight. U.S. Patent 5,177,826 (Vrignaud et al.) reports a pair of disc-like rotary brushes mounted for rotation about an axis generally perpendicular to a length of the handle. Between the rotary pair are upper and lower linear brushes rotating in a linear reciprocating motion generally perpendicular to the axis. A
cylindrical cam element mounted for eccentric rotation operates as part of the system. A further gear is secured to the cam element, but mounted for concentric rotation.
U.S. Patent 5,077,855 (Ambasz) describes an electric 18-05-20010 W~ CA 02374083 2001-11-14 EP 000004' V V J i V \
Amended 9 May 2001 toothbrush including a drive unit having a motor and a transmission that simultaneously drive a shaft and a brushhead extension reciprocally in a direction parallel to the axis of the shaft. A brush unit includes a brushhead coupled to the extension for lengthwise reciprocating motion on which several bristle holders, each carrying several bristle tufts, are mounted individually for pivotal movement about an axis spaced apart from and parallel to the drive shaft. A crank coupled to the drive shaft imparts pivotable movement to each bristle holder individually.
WO 98/23223 (Petz et al.) discloses an electric toothbrush with a drive motor which through a reduction gear system driven by a crank drive moves longitudinally and partly rotates the motor shaft and attachable brush element. A
switch element will momentarily interrupt power to the electric motor to advise a user on the proper pressure applied to the teeth during brushing. Lateral movement is imparted by a camwheel angularly canted in a slot. This system has problems of tolerancing and complexity leading to accelerated wear, unnecessary noise, multiplicity of parts and assembly difficulties.
Even with the options and improvements categorized above, most of the mechanical designs remain complex. Many small parts are required to impart a rotary motion to the bristles or head. Furthermore, the necessarily miniature character of these parts and their unsealed arrangement accelerates wear in the abrasive environment typical of the oral cavity.
Another significant problem is that of efficacy. Electric toothbrushes when compared to the manual variety are not more efficient. For instance, little difference has been seen in their respective tartar removal performance.
AMENDED SHEET

18-05-2001 ~~ Wa CA 02374083 2001-11-14 EP 000004 V V .,I y V \
Amended 9 May 2001 - 3a -Still another major shortcoming of the known art is its non-conformance to best practice toothbrush movement. Most periodontology graduate program textbooks promote the Bass technique. It is recommended for bacterial plaque removal adjacent to and directly beneath the gingival margin. This area is the most significant in the control of gingival and periodontal disease. Elements of the Bass technique include positioning the brush along the gum line at a 45° angle. One AMENDED SHEET
row of the bristles should be nestled slightly under the gums where they meet the teeth. Thereafter the brush is gently wiggled back and forth ten times to loosen plaque within the hidden fold along the gum line. In a final step, the brush is lifted away and repositioned to perform the same motion with the next set of teeth and gums.
Accordingly, it is an object of the present invention to provide an electric toothbrush delivering three dimensional motion to the bristles.
It is another object of the present invention to provide an electric toothbrush delivering a three dimensional motion which conforms to the Bass technique for bacterial plaque removal adjacent to and directly beneath the gingival margin.
Still a further object of the present invention is to provide an electric toothbrush of simpler mechanical design and which permits less costly replacement of brushheads than those normally associated with mechanical drive systems presently in commerce.
These and other objects of the present invention will become more readily apparent through the following summary and detailed description.
Accordingly, a first aspect of the invention provides an electric toothbrush which includes:
(i) an elongate body defining a handle and having an interior cavity formed therein, the cavity extending from a front to a rear end;
(ii) a power source mounted within the cavity;
(iii) an elongate drive shaft aligned from front to rear end driven rotatably by the power source;
(iv) a camwheel mounted on the drive shaft;
(v) a yoke with projecting arms, the camwheel axially reciprocating between the projecting arms thereby imparting a reciprocating movement to the drive shaft ;
(vi) a crankshaft section axially downstream from the yoke and being driven by the drive shaft;
(vii) an output shaft axially aligned with the drive shaft; and (viii)a collar with a guide track eccentrically coupling the crankshaft section to the output shaft thereby imparting both lateral and reciprocating rotary motion to the output shaft.
The mechanical drive system embraces within a closed housing a completely self contained three dimensional system. No mechanical drive aspects are required external to the brush handle housing in order to provide a brushing action.
A simple brushhead is positioned telescopically onto the output shaft. Retention is best achieved by a detent. No moving parts are necessary in the brushhead and it can be formed from a short, hollow shaft.
The combined lateral and reciprocating rotary movement of the output shaft is transmitted to the brushhead. Each individual brush tip fiber of the brushhead is caused to move clockwise in a predicable oval pattern. The fiber tips move in concert to create an overlapping scrubbing pattern.
Travel of the brush tips are conducive to improved cleaning of tooth interstices and gum lines in a manner suggested by the Bass technique.
Advantageously the camwheel is canted between 1 and 20°
relative to the drive shaft. More preferably the cant ranges from 4 to 10°
The output shaft downstream from the collar has a flexible section adjacent the front end of the elongate body.
Bending can occur along that section at an angle between 1 and 40°
Various features, objectives and benefits of the present invention will become more readily apparent through consideration of the following drawing in which:
Fig. 1 is a side elevational view of an electric toothbrush according to the present invention;
Fig. 2 is the toothbrush according to Fig. 1 with a section of the outer housing removed to reveal the drive mechanism;
Fig. 3 is an expanded view of a section along the drive mechanism shown in Fig. 2;

Fig. 4 is a top view of a bristle bundle array; and Fig. 5 is a travel pattern generated when the bristle S bundle array of Fig. 4 is vibrated by the mechanism shown in Fig. 3.
Fig. 1 provides a view of the first embodiment of the present invention. The electric toothbrush shown in this figure includes an elongate body 2 defining a handle 4 and an interior cavity 6 formed within the body. The cavity extends from a front end 8 to a rear end 10. A brushhead member 12 is positioned on the front end of the elongate body retained through a detent 14. The brushhead member includes a bristle bundle array 16 projecting from a head 18.
Brushhead member 12 surrounds flexible shaft 20, the latter representing a terminus of the electric toothbrush drive mechanism. Coupling of the flexible shaft to the brushhead member allows for an ergonomically angled head in respect to the handle 4. Water resistant seal 22 surrounds the flexible shaft to protect the electrical mechanism from the external environment. Within cavity 6 towards the rear end is positioned a miniature motor 24. Battery 26 positioned in close proximity to the motor serves as an energy source.
An induction charging coil 28 is located at the rear end of the elongated body and electrically connected to an electronic control board 30. The battery is rechargeable by connecting the coil to a standard 120 AC outlet source.
Start and stop control buttons 32, 34 are positioned on an 18-05-2001 CA 02374083 2001-11-14 EP 000004' J6516 (V) WO
Amended 9 May 2001 g _ External wall of the elongated body directly above the electronic control.board. A charging light 36 is stationed at a lower end of the control board as an indicator of battery recharge level.
An understanding of details of the drive mechanism assembly 38 can best be understood by review of Fig. 2 in conjunction with Fig. 1. A more detailed view is found in Fig. 3.
Driven gear 42 is positioned adjacent and activated by motor 24. Coupled to the driven gear is a smaller drive gear 44 with a reduction ratio of approximately 2:1 respectively.
other embodiments may utilize reduction gear ratios ranging anywhere from about 10:1 to about 1.2:1. Space considerations place a premium on a minimum number of gears although other embodiments may employ a greater number of reduction gears and in different spatial arrangements.
An elongate drive shaft 46 rotatably communicates from drive gear 44 onto which the latter is force fitted. A camwheel 48 having a central aperture 50 is supported by the drive shaft 46 which force fittingly penetrates the central aperture. Camwheel 48 is positioned at a cant angle of approximately 6°. Bracketing the camwheel is a yoke 52 with arms 54 projecting from a circular mounting base 56. Travel of the camwheel is laterally restricted by placement between the arms of the yoke.
Downstream from the yoke is a crankshaft section 58 drive by the driveshaft 48. Parallel with the reciprocating drive shaft 46 is an output shaft 60.
Eccentrically coupling the crankshaft section to the output AMENDED SHEET

J6516 (V) WO
Amended 9 May 2001 g _ shaft is a collar 62 formed with a guide track 64 through which the crankshaft traverses. Support for the drive mechanism is achieved by a stiff frame 40. Suitable materials for the frame are injection molded plastics such as nylon.
A flexible section 66 of the output shaft downstream from the collar is bent at an angle between 1 and 40°.
Power transmission begins with pressure on the start button activating the battery. Electrical connection causes the motor to rotate transmitting rotational motion via a short shaft to turn the driven gear. The latter couples with the larger drive gear causing rotation in an opposite direction.
Since the drive gear is firmly attached to the drive shaft, the camwheel, in turn, rotates. Outer rims of the camwheel rotate in continuous close contact to the projecting arms of the yoke. The base of the yoke is partially rotatable about its circular axis to accommodate a continuously changing approach angle generated by the camwheel as it rotatingly travels between the yoke arms. A constant fixed contact of the arms is therefore maintained with the rim of the camwheel. As a result, a reciprocating motion of the crankshaft occurs. This motion is then further transmitted to the collar via the crankshaft section spinning eccentrically.
Reciprocating motion of the crankshaft section is thereby transferred directly to the collar and output shaft.
Further, it must be noted that the eccentric crankshaft section acting upon the collar imparts an oscillating motion AMENDED SHEET

to the output shaft in concert with the reciprocating motion. The combination produces a compound motion of the brushhead as it is turned by its shaft through positive engagement with the flexible section of the output shaft.
Fig. 4 displays a top view of the bristle bundle array.
Motion of bristles within the array are shown in Fig. 5.
Substantially overlapping travel paths are generated by the combination of motion generated through the drive assembly mechanism of this invention. Overlapping travel paths closely match the brushing pattern most recommended by dentists. Travel of the brush bristles occurs at relatively high speed producing a multiplicity of overlapping scrubbing strokes. These cross back and forth over a tooth surface.
It is to be understood that bristle arrays other than those illustrated can be suitable for toothbrushes of this invention. The bristles may be cut at angles to facilitate proper brushing of teeth which may lie awkward to reach within the oral cavity. The angle may be further adjusted in combination with the brushhead member to closely conform the angle referred to as the Bass angle A by periodontal and dental practitioners.
The foregoing description and examples illustrate selected embodiments of the present invention. In light thereof variations and modifications will be suggested to one skilled in the art, all of which are within the spirit and purview of this invention.

Claims (6)

1. An electric toothbrush comprising:
(i) an elongate body (2) defining a handle (4) and having an interior cavity (6) formed therein, the cavity extending from a front end (8) to a rear end (10);
(ii) a power source (26) mounted within the cavity;
(iii) an elongate drive shaft (46) aligned from front to rear end driven rotatably by the power source;
(iv) a camwheel (48) mounted on the drive shaft;
(v) a yoke (52) with projecting arms (54), the camwheel axially reciprocating between the projecting arms thereby imparting a reciprocating movement to the drive shaft;
(vi) a crankshaft section (58) axially downstream from the yoke and being driven by the drive shaft (60);
the improvement characterized in further comprising;
(vii) an output shaft (46) parallel with the drive shaft (60); and (viii) a collar (62) with a guide track (64) eccentrically coupling the crankshaft section to the output shaft thereby imparting both lateral and reciprocating rotary motion to the output shaft.
2. The electric toothbrush according to claim 1 wherein the camwheel has a cant between 1 and 20° relative to the drive shaft.
3. The electric toothbrush according to claim 1 or 2 wherein the cant ranges from 4 to 10°.
4. The electric toothbrush according to any of claims 1-3 wherein the output shaft downstream from the collar adjacent the front end has a flexible section (66) allowing bending at an angle between 1 and 40°.
5. The electric toothbrush according to any preceding claim wherein the yoke has a circular mounting base (56) and is partially rotatable.
6. The electric toothbrush according to any preceding claim wherein the brushhead member is replaceably removable from a front end of the elongate body and separated therefrom by a rubber seal (22).
CA002374083A 1999-06-04 2000-05-22 Electric toothbrush Abandoned CA2374083A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US13754199P 1999-06-04 1999-06-04
US60/137,541 1999-06-04
PCT/EP2000/004728 WO2000074592A1 (en) 1999-06-04 2000-05-22 Electric toothbrush

Publications (1)

Publication Number Publication Date
CA2374083A1 true CA2374083A1 (en) 2000-12-14

Family

ID=22477892

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002374083A Abandoned CA2374083A1 (en) 1999-06-04 2000-05-22 Electric toothbrush

Country Status (12)

Country Link
EP (1) EP1182988A1 (en)
JP (1) JP2003501138A (en)
CN (1) CN1353595A (en)
AR (1) AR020567A1 (en)
AU (1) AU4925000A (en)
BR (1) BR0011263A (en)
CA (1) CA2374083A1 (en)
HU (1) HUP0201345A2 (en)
MX (1) MXPA01012367A (en)
PL (1) PL352802A1 (en)
TR (1) TR200103489T2 (en)
WO (1) WO2000074592A1 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1385448A1 (en) * 2001-04-27 2004-02-04 Nordica International AB Electric toothbrush
US20030140437A1 (en) 2002-01-31 2003-07-31 Eyal Eliav Powered toothbrush
US8317424B2 (en) 2004-06-03 2012-11-27 The Gillette Company Oral care device
EP3060162B1 (en) * 2013-10-25 2018-08-29 Koninklijke Philips N.V. Attachment for an electric toothbrush handle and method of attaching
JP2016087393A (en) * 2014-11-10 2016-05-23 杉本 一郎 Electrically-driven periodontal toothbrush
CN110360290A (en) * 2019-08-21 2019-10-22 广东海泰金属制品有限公司 The cam lever power device of speed change output

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1250455A (en) * 1959-10-01 1961-01-13 Brushing device intended in particular for cleaning teeth
US3538530A (en) 1968-01-30 1970-11-10 Braun Ag Toothbrush
US4276672A (en) 1977-11-07 1981-07-07 Teague Jr Walter D Power toothbrush or the like with orbital brush action
US5177826A (en) 1990-03-16 1993-01-12 Hagemann International Rotary toothbrush
US5077855A (en) 1990-06-05 1992-01-07 Emilio Ambasz Motor-driven toothbrush
DE4239251A1 (en) 1992-11-21 1994-05-26 Braun Ag Electric toothbrush with rotating bristle holder
BE1007432A3 (en) 1993-07-30 1995-06-13 Philips Electronics Nv Toothbrush
WO1998023223A1 (en) * 1996-11-25 1998-06-04 Ewt Elektrogeräte Gmbh & Co. Kg Electric tooth brush

Also Published As

Publication number Publication date
HUP0201345A2 (en) 2002-08-28
JP2003501138A (en) 2003-01-14
MXPA01012367A (en) 2002-07-30
BR0011263A (en) 2002-04-02
AU4925000A (en) 2000-12-28
AR020567A1 (en) 2002-05-15
EP1182988A1 (en) 2002-03-06
PL352802A1 (en) 2003-09-08
WO2000074592A1 (en) 2000-12-14
TR200103489T2 (en) 2002-04-22
CN1353595A (en) 2002-06-12

Similar Documents

Publication Publication Date Title
US6446294B1 (en) Electric toothbrush
EP0661954B1 (en) Mechanical toothbrush
EP1489941B1 (en) Powered toothbrush with rotating sections
US5253382A (en) Power operated toothbrush
US6889401B2 (en) Powered toothbrush with vibrating section
US5855216A (en) Dental flossing device
US20130091645A1 (en) Electric Toothbrush
EP2604144A1 (en) Powered toothbrush
ZA200406202B (en) Powered toothbrush.
KR20050065562A (en) Toothbrush
GB2352621A (en) Electric toothbrush : drive to orbit head
MXPA04010446A (en) Powered toothbrush.
JPH02142508A (en) Electric tooth brush
CA2517068C (en) Powered toothbrush with improved ergonomics
US20050076933A1 (en) Motorized flosser and associated method of use
EP0208401B1 (en) Power-driven cleaning brush
CA2374083A1 (en) Electric toothbrush
CN2683063Y (en) three-dimensional electric and manual dual-purpose toothbrush
CA2474394A1 (en) Powered toothbrush
CN2595333Y (en) Multiple side brush head vibrative electric tooth-brush
CN2744317Y (en) Electric toothbrush
KR20030063658A (en) Toothbrush
AU2003207747A1 (en) Powered toothbrush
CA2011718A1 (en) Speed brush

Legal Events

Date Code Title Description
FZDE Discontinued